NATO’s Resilience: How the Alliance Navigated the Trump Years and Beyond

By the end of President Donald Trump’s first term, concerns about a systemic crisis within NATO were widespread. Predictions of the transatlantic security alliance’s demise were commonplace. However, by January 2026, NATO not only survived but had taken on new roles and responsibilities, playing a more significant role in facilitating western military assistance to Ukraine, and potentially expanding its focus to Arctic security. This article examines how NATO navigated the challenges posed by the Trump administration and emerged as a resilient institution.

NATO’s Enduring Institutional Strengths

The 1949 North Atlantic Treaty (NAT) does not automatically obligate signatories to offer military assistance to allies under attack. Article 5 requires each signatory to take “such action as it deems necessary,” allowing for flexibility in response. However, the treaty emphasizes collective security through continuous self-help and mutual aid, as outlined in Article 3. This commitment led to the creation of the North Atlantic Council (NAC), a forum for member state representation and consultation.

Early negotiators, like British diplomat Nicholas Henderson, emphasized the “common purpose” driving western leaders at the time. This was institutionalized through the creation of international political and military staffs and a process for reviewing national defense plans. A 1957 study highlighted this review process as an “unprecedented performance” in multilateral scrutiny and recommendation.

NATO’s development wasn’t about supranationalism but about establishing a “consultative regime” – a set of rules and expectations that regulated member state behavior and policy formulation. This regime, as defined by scholars like Robert Keohane, helped shape how member states conceptualized and implemented security policies.

Historical Challenges to NATO’s Cohesion

During the Cold War, NATO members generally adhered to collective recommendations. Even the United States was willing to adjust planned reductions in response to intra-alliance pressures. By the 1980s, NATO’s consultative and behavioral regimes had become robust. As scholar Glenn Snyder noted, the alliance was stable due to the systemic context of Cold War bipolarity and shared security interests.

The end of the Cold War in 1989-1991 presented a new challenge. Member states reduced defense budgets, seeking a “peace dividend.” However, these reductions occurred within the framework of NATO’s established force-planning process and consultative regimes.

Prior to Donald Trump’s presidency, the George W. Bush administration posed significant questions to NATO’s viability. Bush initially pledged to withdraw American troops from Bosnia and Kosovo, deployments considered crucial for European security. However, allied defense ministers commissioned reviews of force levels, subtly increasing the political costs of unilateral withdrawal. Senior American officials, including Secretary of State Colin Powell, and military officers voiced support for maintaining existing troop levels, influencing Bush to reaffirm his commitment to NATO in 2001, stating, “We came in together, and we will leave together.”

The terrorist attacks of September 11, 2001, triggered a collective NATO response, invoking Article 5 for the first time. NATO agreed on eight measures of practical support for the United States’ “Global War on Terror,” including overflight rights and the deployment of surveillance aircraft and a naval task force. While disagreements over the Iraq War in 2002-2003 existed, they were largely kept out of formal NATO deliberations.

Trump and NATO: A Complex Relationship

Donald Trump’s rhetorical antipathy towards NATO during his 2016 campaign and early presidency was well-documented. Despite this, policy continuity with his predecessors was striking. NATO’s Enhanced Forward Presence (EfP), designed to reassure vulnerable members and deter Russian aggression, continued under Trump, with the US contribution increasing from under $1 billion to over $6 billion during his first term. Concerns about potential troop withdrawals from Germany were addressed through consultations at NATO headquarters, resulting in redeployment to Poland to bolster the EfP.

Several factors contributed to this continuity. Senior Trump administration officials, like Defense Secretary James Mattis, consistently reassured allies of American commitment. Congress also played a crucial role, passing legislation like the NATO Support Act (NSA) in 2019, which restricted the president’s ability to withdraw from NATO without Senate approval. The NSA and subsequent National Defense Authorization Acts (NDAAs) increased funding for the EfP and Ukraine’s defense, and prohibited relinquishing the position of Supreme Allied Commander Europe (SACEUR).

Trump’s criticisms of defense burden-sharing also inadvertently strengthened NATO’s force-planning process. During his first term, all identified capability targets were met by member states, a success attributed to the US working within the established multilateral framework.

By 2025, Trump reached an accommodation with NATO, recognizing the collective framework as a useful means of promoting a fairer division of costs and responsibilities. This was facilitated by NATO Secretary-General Mark Rutte, who brokered agreements on defense spending, military assistance to Ukraine, and potential security responsibilities in Greenland. In July 2025, Trump announced a deal for NATO to purchase weapons from the U.S. To send to Ukraine, with European allies financing the purchases. POLITICO reported this as a significant move in supporting Kyiv.

Conclusions

Despite predictions of its demise, NATO has demonstrated remarkable resilience in the face of challenges, including those posed by the Trump administration. A combination of enduring institutional strengths, restraining factors within the US government, and a willingness to adapt and compromise has allowed the alliance to navigate a period of uncertainty and emerge stronger. The relationship between the US and NATO, while sometimes strained, remains a cornerstone of transatlantic security.