U.S. Treaty Commitments, NATO, and Congressional Responsibility

In January 2019, senior Trump administration officials told the New York Times that during the 2018 Brussels Summit for the North American Treaty Organization (NATO), U.S. President Donald Trump stated “several times” that he wanted to withdraw the United States from NATO. This move would be in stark opposition to bipartisan Congressional support for NATO and strong American public support of the alliance’s utility for U.S. national security. Indeed, few speakers on the floor of Congress can boast that their speech received a bipartisan standing ovation, but NATO’s General Secretary Jens Stoltenberg received just that after his April 2019 speech (see time stamp 58:10) reaffirming the transatlantic relationship and NATO’s pivotal role in western security.

While the American Constitution outlines the proceedings required for the United States to enter international treaties in Article II, Section 2, it does not lay out how the United States should extricate itself from treaties. Therefore, it is possible that any American president could remove the United States from Article II treaties – that is, those formally ratified by two-thirds of the United States Senate – without Congressional approval. That means in theory, any American president could unilaterally remove the United States from NATO, regardless of congressional or public opposition to the move.

Congress and NATO

Under the Trump Administration, the United States has withdrawn from a variety of international treaties and agreements, such as the Joint Comprehensive Plan of Action (JCPOA), Paris Climate Agreement, INF Treaty, and Open Skies Treaty. While the American public’s support for NATO is strong, opinion on the United States’ recent treaty withdrawals has become increasingly politicized and polarized. Therefore, it is important for Congress to consolidate two similar bills on NATO withdrawal: Senate Joint Resolution 4, which bars the president from withdrawing the United States from NATO without the approval of two-thirds of U.S. Senators, and the House’s NATO Support Act, which prohibits funds to be used to withdraw from NATO and states that it is the “sense of Congress” that the president “shall not withdraw the United States from NATO.” 

Ideally, Congress should adopt the “mirror principle” in relation to treaty withdrawals; that is, since Article II treaties require two-thirds of senators to ratify them, then two-thirds of senators should concur with the President’s decision to withdraw from said treaty. This is a component of the Senate’s resolution that is left out of the House bill. The House bill includes welcome language supporting NATO, such as reaffirming American commitment to Article 5 of the Washington Treaty, recognizing NATO as a critical component of American national security, and reiterating that it is American policy to remain a member in good standing of NATO. However, since this bill does not contain the mirror principle requirement, Congress should focus on passing Senate Joint Resolution 4, while reaffirming congressional commitment to NATO in a separate bill. This has been done in the past, such as House Resolution 397 of the 115th Congress that reaffirmed Congress’ commitment to NATO and collective defense.

Possible Implications of a Sudden U.S. Withdrawal from NATO

It is true that Europe is more whole, free, and at peace than at perhaps any time in its history. However, that does not mean that the United States no longer has a role to play in European security. In the event of an American withdrawal from NATO, Europe would be particularly vulnerable in terms of collective defense, especially in the immediate years following withdrawal. 

To explore the implications for a sudden American withdrawal from NATO, the International Institute for Strategic Studies conducted a policy game in July 2019 that sought to roleplay European responses to American withdrawal. In short, European nations fractured on how best to pursue European security. For example, the French viewed NATO as dead after American withdrawal and proposed an European Union-centered security arrangement, but the United Kingdom rejected this proposal outright, stating that it could not accept any European army. Similarly, the United Kingdom, Germany, and Poland all supported maintaining NATO structures, while France did not. Poland, skeptical of Western Europe’s ability to arrange European security, even considered pursuing bilateral defense treaties with the United States, while Germany sought to convince the United Kingdom and France to extend their nuclear deterrents to the rest of Europe. 

Then, the team was presented with a fictional scenario where a NATO member in the Western Balkans experienced a pro-Russian coup and Russian warships blocked access to the Mediterranean. Crucially, the policy game found that European teams struggled to invoke Article 5 and instead opted for Article 4 (which merely calls for consultations) and more sanctions on Russia. That said, all “consistently rejected Russian offers for conflict resolution in exchange for concessions on European security,” showing that all teams did not view Russia as a credible security provider in Europe. Of course, this sequence of events is from just one policy game, but its lessons are important. Immediate and unplanned American withdrawal from NATO would likely throw European security into a tailspin, undermining the continent’s strategic stability that the U.S. sought and constructed after World War II.

NATO’s Benefit to the United States

NATO’s importance to the United States is well documented. However, it is worth repeating that the United States has a strong interest in a stable Europe. For example, even without the United Kingdom in the European Union, the EU is the United States’ largest trading partner. Stability in Europe ensures the uninterrupted flow of goods and capital across the transatlantic community, fostering economic gains on both sides of the Atlantic, a benefit that will be particularly important as both North America and Europe recover from the COVID-19 pandemic. 

Beyond economic benefits, NATO simplifies American alliance structures by placing its transatlantic alliances into one agreement, as opposed to navigating dozens of separate bilateral defense treaties. Relatedly, NATO acts as a forum for transatlantic security dialogues and ensures that the United States has a primary seat at the table regarding European security issues. Lastly, it remains the case that the only time NATO invoked Article 5 was in defense of the United States (not smaller European allies) after 9/11. The benefits to the United States are clear.

Conclusion

The United States may one day withdraw from NATO, but that decision must be made in close consultation with our European and Canadian allies and carefully planned to ensure the transatlantic link remains intact. To ensure that an American president cannot withdraw the United States from NATO unilaterally, and potentially without sufficient planning, Members of Congress should pass Senate Joint Resolution 4 of the 116th Congress. While this does not necessarily guarantee that the president cannot withdraw the nation from NATO, it makes withdrawal more legally challenging and could help prevent the withdrawal unless the administration has a clear, well thought out plan supported by Congress.