A second Trump presidency could radically alter U.S. foreign policy, prioritize national sovereignty, disrupt alliances, and challenge the liberal international order. What will the future hold?
The prospect of a second Trump presidency after the 2024 elections raises considerable speculation about the potential direction of U.S. foreign policy, especially in light of his administration’s substantial departure from traditional U.S. foreign policy practices. Epitomized by an “America First” agenda, Trump prioritized national sovereignty, economic interests, and displayed a disdain for multilateralism. Often, making extensive strategic changes in foreign policy can be challenging due to the complex interplay of domestic and international factors, which create momentum favoring continuity over change. However, in the U.S., the Constitution distributes foreign relations powers between the executive and legislative branches, granting some powers exclusively to the president, others to Congress, while leaving some unassigned.
This separation of powers has led to significant debate over the respective roles and limits of the president and Congress in foreign affairs, particularly on issues such as military operations, foreign aid, intelligence, international agreements, trade, and immigration. For example, while only Congress can declare war, U.S. presidents, in the post-9/11 era, have ordered military forces into conflicts such as Iraq, Libya, and Syria without congressional authorization. Similarly, in the domain of immigration, U.S. presidents are constitutionally bound to execute federal immigration laws, but there is much debate over how much latitude they have in doing so. For instance, Republican lawmakers criticized the Obama administration for ignoring the law when it established programs shielding undocumented immigrants from deportation. Likewise, many Democratic lawmakers said Trump overstepped his constitutional and statutory authority when he attempted to block migration from seven Muslim-majority countries. Given that substantive influence on foreign policy in the post-Cold War period has tended to typically, though not always, fall to the president, there have been radical shifts in U.S. foreign policy, with the trend of executive dominance reaching new heights under Trump.
Alas, the conflict between the executive branch of government and the U.S. Congress on foreign policy has often been referred to the federal courts, including the Supreme Court, to provide interpretations on questions involving foreign affairs powers. Yet, even in such circumstances, the courts operate under very strict judicial restraints, especially in cases the courts deem as “political questions.” For example, in one of the disputes that involved the Obama administration and Congress over the recognition of Israeli sovereignty over Jerusalem, the court argued that only the U.S. president “could make the specific decision of what foreign power he will recognize as legitimate.” Furthermore, beyond the discourse on which institution wields more influence, there has been debate on what the nature of U.S. foreign policy should be. In the immediate post-Cold War period, when the U.S. was the only genuinely global power across military, political, economic, and socio-cultural spectrums, proponents of an isolated U.S. foreign policy argued that such an approach carried the strategic advantage of avoiding the constraints that come with seeking international cooperation, thus enabling swift and decisive American responses to international challenges. On the other hand, globalists argued that despite American primacy in world affairs, global interconnectedness and interdependence created complexities that necessitated multilateral cooperation.
To understand the potential foreign policy trajectory of a second Trump term, it is imperative to explore key elements of his initial tenure, which was characterized by an agenda to reassert American power while simultaneously reducing its international commitments. His administration’s economic and trade policy was perhaps the most defining foreign policy element, in which he emphasized the “protection of American industries and jobs” through the use of tariffs and trade wars. The withdrawal from the trade-oriented Trans-Pacific Partnership (TPP), the climate-focused Paris Agreement, and the renegotiation of NAFTA—which he termed the “worst trade deal ever made”—into the United States-Mexico-Canada Agreement (USMCA) were pivotal moments that demonstrated his preference for bilateral over multilateral agreements. Trump sustained his critique of many international commitments, asserting that bilateral partners and multilateral institutions were taking advantage of the U.S. for security guarantees and trade agreements. This skepticism led to additional U.S. withdrawals from key international arrangements such as the World Health Organization (WHO), and his administration’s subsequent hardline stance against NATO, even going as far as questioning the value of the alliance.
For Trump, international institutions have tended to constrain rather than amplify American power, thus reverting to unilateralism was seen as imperative to give the U.S. more leverage to take decisive actions. Indeed, this unilateralism was evident in the killing of Iran’s most powerful military commander, General Qassem Soleimani, pressuring Britain into excluding the Chinese firm Huawei, compelling NATO allies to increase their contributions to collective defense, and pressuring Canada and Mexico to renegotiate NAFTA. However, on the broader spectrum of U.S. foreign policy, these “successes” came with far-reaching implications. While Europe has been unable to counter America’s financial power, it did not comply with Trump’s demand to abandon the Joint Comprehensive Plan of Action (JCPOA) nuclear deal with Iran, which remains tenuously intact. Additionally, despite significant American pressure, Iran has not been forced to negotiate on American terms even after the death of General Soleimani. Moreover, while NATO countries are contributing more to defense, France and Germany are now advocating for Europe to accelerate efforts to build a more autonomous defense capability and reduce their reliance on the U.S. for security.
Repeatedly, the insistence on demonstrating American strength, on winning, and on being seen as victorious had unintended impacts. Trump came to power promising to end what he described as Washington’s naïveté, which he claimed was enriching the rest of the world at America’s expense. He vowed to be a great dealmaker. However, his record shows more deals destroyed than created. Even on issues where Trump might have enjoyed broad international support—such as nuclear disarmament and countering Chinese aggression—he undermined agreements and alienated allies. He waged a trade war against China largely on his own, announced the drawdown of American forces from Germany without prior notification to Berlin, and sought to dismantle the Iran nuclear deal single-handedly. This unwavering commitment to unilateralism forced American allies to alter their behavior and disrupted their long-held faith in the U.S.-led Western alliance.
As Americans head to the polls in November 2024, one question that has encapsulated observers of U.S. foreign policy is what it would look like under a second Trump presidency. Based on precedent, if Trump were to win, it is likely that his primal instincts would be fully at play, perhaps reflecting continuity with his administration’s foreign policy during his first term in office.
Regarding the Trans-Atlantic alliance, there is no doubt that Trump has, in the past, raised legitimate concerns about the sustainability of U.S. global obligations as part of multilateral alliances. However, what seems to elude the former president is that America’s desire to provide global leadership comes with greater commitment, especially in the midst of an international system that has transformed substantially. Indeed, while American power is still the greatest, it has nonetheless waned compared to a decade ago, and even more so compared to the decade before that. Thus, while there is logic in seeking to withdraw from some of its grand strategic commitments, doing so comes at the cost of accelerated and diminished global influence.
In the past, Trump has threatened to oversee the withdrawal of the U.S. from NATO, to the point where Congress became concerned and passed legislation making it impossible for presidents to pull out of the alliance without the approval of the Senate or an Act of Congress. However, this barely allays concerns, because the issue is not just whether Trump would try to have the U.S. leave the alliance, but whether it would act in concert with its NATO partners. It is likely that Trump will not only call for a drastic increase in NATO spending by allies but also seek a radical reorientation of the alliance. This could, for instance, take the shape of an American commitment to provide a nuclear umbrella in Europe and guarantee airpower through its existing bases in Turkey, Germany, and England, in exchange for shifting the bulk of infantry, logistics, and artillery roles to allies. This would drastically reduce the security role of the U.S. within the alliance, except in times of great crisis.
Moreover, this radical reorientation may also take the form of a refusal by the U.S. to commit to Article 5 of the NATO treaty in the event of an attack on members that have not yet met the target of spending 2 percent of GDP on defense, due to at least two important reasons. First, invoking Article 5 requires consensus, meaning it can only be operational if all members agree that an attack has occurred and authorize action. The disagreement of one member, especially a powerful one, could therefore thwart consensus. Second, even in the event that Article 5 is invoked, the provision for members to respond as “deemed necessary” provides flexibility that could allow a member to refrain from providing substantive support.
Beyond the scope of Article 5, a second Trump presidency may put additional pressure on NATO’s deterrence role. In the past, particularly during the Cold War, NATO was considered to have successfully deterred an attack by the Soviet Union, and this deterrence has also largely been effective against plans for a conventional attack by Russia on the alliance, including during a time when the alliance is providing substantial military support to Ukraine. To a large extent, this deterrence is anchored on the American nuclear umbrella, which acts as a key deterrent to Russia. However, a second Trump presidency would raise concerns about this deterrence policy, given his past comments telling Russia to “do whatever the hell they want” against allies who don’t spend enough on their defense. Although France and the UK have nuclear capabilities, they do not provide the same level of deterrence as the U.S. does against Russia.
Trade and economic policy have consistently been central to Trump’s agenda and manifested in the form of economic nationalism. Indeed, while his stance on various other issues has evolved over time, his focus on trade has remained constant. During his first term in office, Trump’s success in advancing his trade agenda was facilitated by the unique aspects of the U.S. political system and Constitution, which, despite granting Congress clear authority over taxation (including tariffs), also allows considerable flexibility for a president and the executive branch to take action on trade and economic matters. Part of Trump’s rhetoric prior to and during his first term in office was that he is a “tough and shrewd” negotiator in business, and that he would do away with trade policies that largely benefited other countries at the expense of U.S. economic interests. In 2018, he tweeted (now on X) that “trade wars are good, and easy to win,” after signing a series of executive actions that imposed tariffs on imported metals from Canada, Mexico, the EU, India, and China. However, given the influence of the U.S. economy, domestic economic policies have tended to have far-reaching implications on the global economy. Thus, the unprecedented imposition of tariffs on key bilateral trade partners triggered reciprocal tariffs on U.S.-produced commodities such as motorcycles, whiskey, juices, and soybeans. The impact of this economic reciprocity was so significant that the U.S. administration disbursed USD 28 billion to farmers to mitigate the losses incurred from the trade war with China.
Yet, during his campaigns, Trump has reiterated his intention to extend the trade wars to an even greater degree, proposing to implement a universal baseline tariff of 10 percent on the majority of foreign products and specifically 60 percent or more on products imported from China. Additionally, Trump has proposed several additional tax cuts, including eliminating federal income taxes on Social Security benefits, the money service workers like waiters and ride-share drivers earn from tips, and has promised to reduce the corporate income tax rate from 21 percent, which he had approved in 2017, to 15 percent. For Trump, bolstering the U.S. economy necessitates creating additional jobs, and imposing higher tariffs on foreign goods would encourage more domestic production, create more local jobs, and reduce the import-export gap. However, despite Trump’s insistence on the continuation of this international trade policy, research shows that while there was success in reducing imports and increased production in some industries like steel and semiconductors, the tariffs nonetheless resulted in higher consumer and production prices for factories dependent on imported inputs. Moreover, due to retaliation, exports of certain U.S. products also declined.
The re-election of Trump in the forthcoming elections could have far-reaching implications for the international order, which has largely been anchored on multilateralism, alliances, and the promotion of democratic values. These tenets, however, appear to be in direct conflict with Trump’s foreign policy priorities, which mainly emphasize national sovereignty, economic nationalism, and a transactional approach to international relations. It is likely that a second term for Trump could accelerate the further decline of the liberal international order, as the U.S. continues to undermine and even withdraw from multilateral institutions and agreements. On a structural governance level, this trend could lead to the disintegration of the global order into a multipolar world, where power is concentrated in regional blocs or individual states, potentially creating an unpredictable and unstable international environment, with a greater potential for conflict and competition between major powers.
A second Trump presidency could radically alter U.S. foreign policy, prioritize national sovereignty, disrupt alliances, and challenge the liberal international order. What will the future hold?
The prospect of a second Trump presidency after the 2024 elections raises considerable speculation about the potential direction of U.S. foreign policy, especially in light of his administration’s substantial departure from traditional U.S. foreign policy practices. Epitomized by an “America First” agenda, Trump prioritized national sovereignty, economic interests, and displayed a disdain for multilateralism. Often, making extensive strategic changes in foreign policy can be challenging due to the complex interplay of domestic and international factors, which create momentum favoring continuity over change. However, in the U.S., the Constitution distributes foreign relations powers between the executive and legislative branches, granting some powers exclusively to the president, others to Congress, while leaving some unassigned.
This separation of powers has led to significant debate over the respective roles and limits of the president and Congress in foreign affairs, particularly on issues such as military operations, foreign aid, intelligence, international agreements, trade, and immigration. For example, while only Congress can declare war, U.S. presidents, in the post-9/11 era, have ordered military forces into conflicts such as Iraq, Libya, and Syria without congressional authorization. Similarly, in the domain of immigration, U.S. presidents are constitutionally bound to execute federal immigration laws, but there is much debate over how much latitude they have in doing so. For instance, Republican lawmakers criticized the Obama administration for ignoring the law when it established programs shielding undocumented immigrants from deportation. Likewise, many Democratic lawmakers said Trump overstepped his constitutional and statutory authority when he attempted to block migration from seven Muslim-majority countries. Given that substantive influence on foreign policy in the post-Cold War period has tended to typically, though not always, fall to the president, there have been radical shifts in U.S. foreign policy, with the trend of executive dominance reaching new heights under Trump.
Alas, the conflict between the executive branch of government and the U.S. Congress on foreign policy has often been referred to the federal courts, including the Supreme Court, to provide interpretations on questions involving foreign affairs powers. Yet, even in such circumstances, the courts operate under very strict judicial restraints, especially in cases the courts deem as “political questions.” For example, in one of the disputes that involved the Obama administration and Congress over the recognition of Israeli sovereignty over Jerusalem, the court argued that only the U.S. president “could make the specific decision of what foreign power he will recognize as legitimate.” Furthermore, beyond the discourse on which institution wields more influence, there has been debate on what the nature of U.S. foreign policy should be. In the immediate post-Cold War period, when the U.S. was the only genuinely global power across military, political, economic, and socio-cultural spectrums, proponents of an isolated U.S. foreign policy argued that such an approach carried the strategic advantage of avoiding the constraints that come with seeking international cooperation, thus enabling swift and decisive American responses to international challenges. On the other hand, globalists argued that despite American primacy in world affairs, global interconnectedness and interdependence created complexities that necessitated multilateral cooperation.
To understand the potential foreign policy trajectory of a second Trump term, it is imperative to explore key elements of his initial tenure, which was characterized by an agenda to reassert American power while simultaneously reducing its international commitments. His administration’s economic and trade policy was perhaps the most defining foreign policy element, in which he emphasized the “protection of American industries and jobs” through the use of tariffs and trade wars. The withdrawal from the trade-oriented Trans-Pacific Partnership (TPP), the climate-focused Paris Agreement, and the renegotiation of NAFTA—which he termed the “worst trade deal ever made”—into the United States-Mexico-Canada Agreement (USMCA) were pivotal moments that demonstrated his preference for bilateral over multilateral agreements. Trump sustained his critique of many international commitments, asserting that bilateral partners and multilateral institutions were taking advantage of the U.S. for security guarantees and trade agreements. This skepticism led to additional U.S. withdrawals from key international arrangements such as the World Health Organization (WHO), and his administration’s subsequent hardline stance against NATO, even going as far as questioning the value of the alliance.
For Trump, international institutions have tended to constrain rather than amplify American power, thus reverting to unilateralism was seen as imperative to give the U.S. more leverage to take decisive actions. Indeed, this unilateralism was evident in the killing of Iran’s most powerful military commander, General Qassem Soleimani, pressuring Britain into excluding the Chinese firm Huawei, compelling NATO allies to increase their contributions to collective defense, and pressuring Canada and Mexico to renegotiate NAFTA. However, on the broader spectrum of U.S. foreign policy, these “successes” came with far-reaching implications. While Europe has been unable to counter America’s financial power, it did not comply with Trump’s demand to abandon the Joint Comprehensive Plan of Action (JCPOA) nuclear deal with Iran, which remains tenuously intact. Additionally, despite significant American pressure, Iran has not been forced to negotiate on American terms even after the death of General Soleimani. Moreover, while NATO countries are contributing more to defense, France and Germany are now advocating for Europe to accelerate efforts to build a more autonomous defense capability and reduce their reliance on the U.S. for security.
Repeatedly, the insistence on demonstrating American strength, on winning, and on being seen as victorious had unintended impacts. Trump came to power promising to end what he described as Washington’s naïveté, which he claimed was enriching the rest of the world at America’s expense. He vowed to be a great dealmaker. However, his record shows more deals destroyed than created. Even on issues where Trump might have enjoyed broad international support—such as nuclear disarmament and countering Chinese aggression—he undermined agreements and alienated allies. He waged a trade war against China largely on his own, announced the drawdown of American forces from Germany without prior notification to Berlin, and sought to dismantle the Iran nuclear deal single-handedly. This unwavering commitment to unilateralism forced American allies to alter their behavior and disrupted their long-held faith in the U.S.-led Western alliance.
As Americans head to the polls in November 2024, one question that has encapsulated observers of U.S. foreign policy is what it would look like under a second Trump presidency. Based on precedent, if Trump were to win, it is likely that his primal instincts would be fully at play, perhaps reflecting continuity with his administration’s foreign policy during his first term in office.
Regarding the Trans-Atlantic alliance, there is no doubt that Trump has, in the past, raised legitimate concerns about the sustainability of U.S. global obligations as part of multilateral alliances. However, what seems to elude the former president is that America’s desire to provide global leadership comes with greater commitment, especially in the midst of an international system that has transformed substantially. Indeed, while American power is still the greatest, it has nonetheless waned compared to a decade ago, and even more so compared to the decade before that. Thus, while there is logic in seeking to withdraw from some of its grand strategic commitments, doing so comes at the cost of accelerated and diminished global influence.
In the past, Trump has threatened to oversee the withdrawal of the U.S. from NATO, to the point where Congress became concerned and passed legislation making it impossible for presidents to pull out of the alliance without the approval of the Senate or an Act of Congress. However, this barely allays concerns, because the issue is not just whether Trump would try to have the U.S. leave the alliance, but whether it would act in concert with its NATO partners. It is likely that Trump will not only call for a drastic increase in NATO spending by allies but also seek a radical reorientation of the alliance. This could, for instance, take the shape of an American commitment to provide a nuclear umbrella in Europe and guarantee airpower through its existing bases in Turkey, Germany, and England, in exchange for shifting the bulk of infantry, logistics, and artillery roles to allies. This would drastically reduce the security role of the U.S. within the alliance, except in times of great crisis.
Moreover, this radical reorientation may also take the form of a refusal by the U.S. to commit to Article 5 of the NATO treaty in the event of an attack on members that have not yet met the target of spending 2 percent of GDP on defense, due to at least two important reasons. First, invoking Article 5 requires consensus, meaning it can only be operational if all members agree that an attack has occurred and authorize action. The disagreement of one member, especially a powerful one, could therefore thwart consensus. Second, even in the event that Article 5 is invoked, the provision for members to respond as “deemed necessary” provides flexibility that could allow a member to refrain from providing substantive support.
Beyond the scope of Article 5, a second Trump presidency may put additional pressure on NATO’s deterrence role. In the past, particularly during the Cold War, NATO was considered to have successfully deterred an attack by the Soviet Union, and this deterrence has also largely been effective against plans for a conventional attack by Russia on the alliance, including during a time when the alliance is providing substantial military support to Ukraine. To a large extent, this deterrence is anchored on the American nuclear umbrella, which acts as a key deterrent to Russia. However, a second Trump presidency would raise concerns about this deterrence policy, given his past comments telling Russia to “do whatever the hell they want” against allies who don’t spend enough on their defense. Although France and the UK have nuclear capabilities, they do not provide the same level of deterrence as the U.S. does against Russia.
Trade and economic policy have consistently been central to Trump’s agenda and manifested in the form of economic nationalism. Indeed, while his stance on various other issues has evolved over time, his focus on trade has remained constant. During his first term in office, Trump’s success in advancing his trade agenda was facilitated by the unique aspects of the U.S. political system and Constitution, which, despite granting Congress clear authority over taxation (including tariffs), also allows considerable flexibility for a president and the executive branch to take action on trade and economic matters. Part of Trump’s rhetoric prior to and during his first term in office was that he is a “tough and shrewd” negotiator in business, and that he would do away with trade policies that largely benefited other countries at the expense of U.S. economic interests. In 2018, he tweeted (now on X) that “trade wars are good, and easy to win,” after signing a series of executive actions that imposed tariffs on imported metals from Canada, Mexico, the EU, India, and China. However, given the influence of the U.S. economy, domestic economic policies have tended to have far-reaching implications on the global economy. Thus, the unprecedented imposition of tariffs on key bilateral trade partners triggered reciprocal tariffs on U.S.-produced commodities such as motorcycles, whiskey, juices, and soybeans. The impact of this economic reciprocity was so significant that the U.S. administration disbursed USD 28 billion to farmers to mitigate the losses incurred from the trade war with China.
Yet, during his campaigns, Trump has reiterated his intention to extend the trade wars to an even greater degree, proposing to implement a universal baseline tariff of 10 percent on the majority of foreign products and specifically 60 percent or more on products imported from China. Additionally, Trump has proposed several additional tax cuts, including eliminating federal income taxes on Social Security benefits, the money service workers like waiters and ride-share drivers earn from tips, and has promised to reduce the corporate income tax rate from 21 percent, which he had approved in 2017, to 15 percent. For Trump, bolstering the U.S. economy necessitates creating additional jobs, and imposing higher tariffs on foreign goods would encourage more domestic production, create more local jobs, and reduce the import-export gap. However, despite Trump’s insistence on the continuation of this international trade policy, research shows that while there was success in reducing imports and increased production in some industries like steel and semiconductors, the tariffs nonetheless resulted in higher consumer and production prices for factories dependent on imported inputs. Moreover, due to retaliation, exports of certain U.S. products also declined.
The re-election of Trump in the forthcoming elections could have far-reaching implications for the international order, which has largely been anchored on multilateralism, alliances, and the promotion of democratic values. These tenets, however, appear to be in direct conflict with Trump’s foreign policy priorities, which mainly emphasize national sovereignty, economic nationalism, and a transactional approach to international relations. It is likely that a second term for Trump could accelerate the further decline of the liberal international order, as the U.S. continues to undermine and even withdraw from multilateral institutions and agreements. On a structural governance level, this trend could lead to the disintegration of the global order into a multipolar world, where power is concentrated in regional blocs or individual states, potentially creating an unpredictable and unstable international environment, with a greater potential for conflict and competition between major powers.
Billy Agwanda is a PhD Presidential Scholar at Carter School, George Mason University, and a co-author of the book “The Somalia Conflict Revisited: Trends and Complexities of Spatial Governance on National and Regional Security.”
