Throughout Donald Trump's presidential campaign and into the first months of his presidency, he has warned that the United States' commitment to the North Atlantic Treaty Organization (NATO) may depend on whether its partner states increase their defense spending in line with previously adopted guidelines. While senior administration officials have reaffirmed U.S. commitments to the NATO alliance, including the North Atlantic Treaty's mutual defense obligation on several occasions,Footnote 1 President Trump himself did not so until mid-June. Separately, the Trump administration signaled its support for NATO by supporting the admission of Montenegro as a new member state.
The North Atlantic Treaty does not impose a quantitative requirement for defense spending. Article 3 provides:
In order more effectively to achieve the objectives of this Treaty, the Parties, separately and jointly, by means of continuous and effective self-help and mutual aid, will maintain and develop their individual and collective capacity to resist armed attack.Footnote 2
This treaty obligation has been supplemented by various subsequent agreements. In 2006, NATO member states made a political commitment to spending at least 2 percent of their gross domestic product (GDP) on defense.Footnote 3 In 2014, the heads of state present at the meeting of the North Atlantic Council in Wales reiterated and expanded upon this commitment. An excerpt follows:
Allies currently meeting the NATO guideline to spend a minimum of 2% of their Gross Domestic Product (GDP) on defence will aim to continue to do so. … Allies whose current proportion of GDP spent on defence is below this level will: halt any decline in defence expenditure; aim to increase defence expenditure in real terms as GDP grows; aim to move towards the 2% guideline within a decade [i.e., by 2024] with a view to meeting their NATO Capability Targets and filling NATO's capability shortfalls.Footnote 4
Also included in the Wales Summit Declaration was a political commitment to spend at least 20 percent of defense spending on major new equipment and/or the research and development of such equipment:
Allies spending more than 20% of their defence budgets on major equipment, including related Research & Development, will continue to do so. … Allies who currently spend less than 20% of their annual defence spending on major new equipment, including related Research & Development, will aim, within a decade, to increase their annual investments to 20% or more of total defence expenditures.Footnote 5
As of February 2017, only five NATO countries, including the United States, were meeting the 2 percent guideline.Footnote 6 Three more are on track to meet that guideline within a year or two.Footnote 7 Among the remaining member states, seventeen have recently begun to increase their defense spending.Footnote 8 Thus, a growing number of NATO member states appear to be in a position to meet the 2 percent guideline before the 2024 deadline agreed to in Wales.
As a presidential candidate, Donald Trump described NATO as “obsolete,”Footnote 9 and complained that the United States pays “a totally disproportionate share of NATO.”Footnote 10 A few days later, he told a crowd at a rally that other NATO member states were “ripping off the United States.”Footnote 11 He concluded that “[e]ither they have to pay up for past deficiencies or they have to get out.”Footnote 12
Since his inauguration, President Trump and other administration officials have continued to raise the defense spending issue. On February 15, 2017, Secretary of Defense Jim Mattis addressed the commitments of the United States and other NATO members:
I register the concern in European capitals about America's commitment to NATO and the security of Europe. I also understand our long-term European allies and friends are seeking reassurance and clarity about American intentions. I join you today representing America's commitment and President Trump's “strong support” for our Alliance.
A decade ago, when I was serving as Supreme Allied Commander for Transformation, I watched then-Secretary of Defense Robert Gates warn members of this Council that Congress and the American body politic would lose their patience for carrying a disproportionate burden of the defense of Allies. …
The impatience Secretary Gates predicted is now a governmental reality. As noted by a European Minister of Defense, calling for two percent defense spending is a “fair” demand from the American people to their long-time Allies and friends in Europe. No longer can the American taxpayer carry a disproportionate share of the defense of western values. Americans cannot care more for your children's future security than you do. Disregard for military readiness demonstrates a lack of respect for ourselves, for the Alliance, and for the freedoms we inherited, which are now clearly threatened.
…
I owe it to you to give you clarity on the political reality in the United States, and to state the fair demand from my country's people in concrete terms. America will meet its responsibilities, but if your nations do not want to see America moderate its commitment to this Alliance, each of your capitals needs to show support for our common defense.
Specifically, we must ensure we are not in the same spot at the end of the year that we are in today. We must adopt a plan this year, including milestone dates, to make steady progress toward meeting Warsaw and Wales commitments.
If your nation meets the two percent target, we need your help to get other allies there. If you have a plan to get there, our Alliance is counting on you to accelerate your efforts and show bottom-line results. And if you do not yet have a plan, it is important to establish one soon. Showing immediate and steady progress to honor commitments made at Warsaw and Wales must become a reality if we are to sustain a credible Alliance and adequately defend ourselves.
… NATO will remain strong only if all nations show their respect for NATO's benefits and carry a full and equal burden of our defense. There is no substitute for our security—and we can afford peace and survival as free nations.Footnote 13
Vice President Mike Pence echoed Mattis's key points in a speech and press conference in Europe later that same month.Footnote 14 On February 20, 2017, NATO Secretary General Stoltenberg also emphasized the importance of burden-sharing:
At the same time, I fully support what has been underlined by President Trump and by Vice President Pence today, the importance of burden-sharing. And I think we have to remember that this is not only something that the U.S. is asking for, it's actually something that 28 Allies agreed. The leaders from 28 NATO-allied countries sat around the same table in 2014 and agreed to stop the cuts, to gradually increase defense spending, and then to meet the 2 percent target within a decade. And the good news is that we are moving in the right direction. After many years of decline, after many years of defense cuts across Europe and Canada, we saw that in 2015 we stopped the cuts, the first year after we made the pledge. And then, in 2016, we had a significant increase of 3.8 percent in real terms, or $10 billion. There is a long way to go, and much remains to be done, but at least we have turned a corner and we have started to move in the right direction. I am encouraged by that, and I expect all allies to make good on the promise that they made in 2014 to increase defense spending and to make sure to have a fairer burden-sharing.Footnote 15
Neither Mattis nor Pence elaborated on what Mattis had in mind when he said that the United States may “moderate its commitment[s]” if other NATO member states failed to meet the 2 percent guideline.Footnote 16 As a candidate, President Trump hinted at the possibility that the United States might refuse to fulfill its collective-defense obligations in the event of an attack against a “massive nation[]” with “tremendous wealth” that hadn't been spending adequately on defense.Footnote 17 These collective-defense obligations are codified in Article 5 of the North Atlantic Treaty, which provides:
The Parties agree that an armed attack against one or more of them in Europe or North America shall be considered an attack against them all and consequently they agree that, if such an armed attack occurs, each of them, in exercise of the right of individual or collective self-defence recognised by Article 51 of the Charter of the United Nations, will assist the Party or Parties so attacked by taking forthwith, individually and in concert with the other Parties, such action as it deems necessary, including the use of armed force, to restore and maintain the security of the North Atlantic area.Footnote 18
Another possibility would be to withdraw troops from—or stop deploying new troops to—countries that are not meeting the 2 percent guideline. Addressing this possibility, the senior NATO commander based in the United States said: “If the U.S. forces would stop deploying, it would be some kind of strategic shock in Europe.”Footnote 19 The United States might also withdraw some of its equipment based in Germany, which hosts the largest contingent of U.S. military personnel in Europe.Footnote 20 Since the U.S. military relies on its military personnel and bases in Germany for operations beyond the scope of NATO,Footnote 21 however, independent strategic considerations may weigh against such a withdrawal.
President Trump's displeasure with NATO partners resurfaced again in March. Following a meeting with German Chancellor Angela Merkel, President Trump tweeted: “Germany owes … vast sums of money to NATO & the United States must be paid more for the powerful, and very expensive, defense it provides to Germany!”Footnote 22 German defense minister Ursula von der Leyen responded:
There is no debt account in NATO. To relate the 2% defense spending that we want to reach in the next decade solely to NATO is wrong … . The defense spending also goes to UN-peace mission[s], into European missions and towards our contributions to the fight against ISIS terrorism.Footnote 23
German Chancellor Angela Merkel has reiterated Germany's commitment to meeting the 2 percent guideline by 2024Footnote 24 and German Defense Minister Ursula von der Leyen described the United States' demand for more spending as “a fair request” and agreed that “[e]veryone has to make a contribution.”Footnote 25 Many German officials see the goal as unrealistic, however.Footnote 26 On March 31, German foreign minister Sigmar Gabriel said
The idea that Germany in a few years will spend €70 billion each year on the army is an idea that I consider absurd … . It's particularly absurd if we look at France which spends €40 billion but has also a nuclear program included in it. I would honestly not even know where to put all the aircraft carriers we would buy with €70 billion.Footnote 27
He went on to emphasize the nature of the spending commitment in the Wales Declaration:
It is important to correctly quote the Wales declaration. Its guidelines say members should lean towards a 2 percent spending, but it is at no point written that this is a fixed goal and that every member state should invest 2 percent of its GDP in defense.Footnote 28
German leaders also endorsed a broad interpretation of the types of expenses that should be counted for purposes of meeting the 2 percent goal. Defense Minister Leyen emphasized that German expenditure on UN peacekeeping missions is part of a “modern understanding of security.”Footnote 29 German leaders, including Chancellor Merkel and Foreign Minister Gabriel, have pointed out that if Germany's €30–40 billion in spending on the Syrian refugee crisis were included in the NATO security spending calculations, Germany would already be either at or very close to the 2 percent guideline.Footnote 30 Italian Foreign Minister Angelino Alfano has made a similar point about Italian spending on search-and-rescue operations for migrants in the Mediterranean.Footnote 31 In addition, European officials have suggested that foreign development aid—an area where the EU's spending exceeds that of the United StatesFootnote 32 —might properly be understood as part of security spending. At the Munich Security Conference in February, Chancellor Merkel said:
When we help people in their home countries to live a better life and thereby prevent crises, this is also a contribution to security … . So I will not be drawn into a debate about who is more military-minded and who is less.Footnote 33
European Commission President Jean-Claude Juncker has also endorsed a broader understanding of European contributions to stability and security.Footnote 34
At a press conference on April 12, 2017, President Trump suggested that his views on NATO may have evolved. Most significantly, he explicitly abandoned his earlier characterization of NATO as obsolete. At a joint press conference with Stoltenberg, Trump declared: “I said it was obsolete; it's no longer obsolete.”Footnote 35 Trump also took a softer tone but retained his focus on spending, saying:
In facing our common challenges, we must also ensure that NATO members meet their financial obligations and pay what they owe. Many have not been doing that. The Secretary General and I agree that other member nations must satisfy their responsibility to contribute 2 percent of GDP to defense. If other countries make their fair share, instead of relying on the United States to make up the difference, we will all be much more secure and our partnership will be made that much stronger.Footnote 36
On May 25, 2017, President Trump attended a NATO summit and personally met with other foreign leaders. His remarks again focused on spending:
The NATO of the future must include a great focus on terrorism and immigration, as well as threats from Russia and on NATO's eastern and southern borders. These grave security concerns are the same reason that I have been very, very direct with Secretary Stoltenberg and members of the Alliance in saying that NATO members must finally contribute their fair share and meet their financial obligations, for 23 of the 28 member nations are still not paying what they should be paying and what they're supposed to be paying for their defense.
This is not fair to the people and taxpayers of the United States. And many of these nations owe massive amounts of money from past years and not paying in those past years. Over the last eight years, the United States spent more on defense than all other NATO countries combined. If all NATO members had spent just 2 percent of their GDP on defense last year, we would have had another $119 billion for our collective defense and for the financing of additional NATO reserves.
We should recognize that with these chronic underpayments and growing threats, even 2 percent of GDP is insufficient to close the gaps in modernizing, readiness, and the size of forces. We have to make up for the many years lost. Two percent is the bare minimum for confronting today's very real and very vicious threats. If NATO countries made their full and complete contributions, then NATO would be even stronger than it is today, especially from the threat of terrorism.Footnote 37
An omission in Trump's speech garnered significant attention: at no point did he reaffirm the United States' obligations under Article 5. According to press reports, that affirmation was deleted shortly before Trump spoke, though it is unclear by whom.Footnote 38 More recently, Vice President Mike Pence specifically reaffirmed the United States' commitment to Article 5, saying:
We will meet our obligations to our people to provide for the collective defense of all our allies.
The United States is resolved, as we were at NATO's founding and in every hour since, to live by that principle that an attack on one of us is an attack on us all.Footnote 39
On June 9, 2017, at a joint press conference with the Romanian president, President Trump finally reaffirmed the U.S. commitment to NATO's collective defense obligation when he said, in response to a question from a journalist:
Well, I'm committing the … United States to Article 5. And certainly we are there to protect. And that's one of the reasons that I want people to make sure we have a very, very strong force by paying the kind of money necessary to have that force. But, yes, absolutely, I'd be committed to Article 5.Footnote 40
Separately, the U.S. Senate and President Trump have evinced their continued support for the Alliance by approving Montenegro's membership in NATO.Footnote 41 Pursuant to the North Atlantic Treaty, the members of NATO may, by a unanimous decision, invite “any other European State in a position to further the principles of this Treaty and to contribute to the security of the North Atlantic area to accede to th[e] [t]reaty …” and thereby become a member of NATO.Footnote 42
Montenegro began the process to join NATO eight years ago, in 2009, when it joined the Membership Action Plan, NATO's program of advice and assistance to prepare countries to join NATO.Footnote 43 Throughout the process, Russia has firmly and vocally opposed to NATO's expansion in the Balkans.Footnote 44 The current NATO members extended such a formal membership invitation to Montenegro on May 19, 2016, by signing an accession protocol.Footnote 45
When President Harry Truman initially submitted the North Atlantic Treaty to the U.S. Senate for its advice and consent in 1949, he committed to seeking the such advice and consent again for the addition of any new members of NATO.Footnote 46 Accordingly, on June 28, 2016, then-President Barack Obama and then-Secretary of State Kerry submitted the accession protocol to the Senate for its approval.Footnote 47 On March 28, 2017, the Senate approved Montenegro's accession by a vote of 97–2.Footnote 48
Following the Report of the Senate Committee on Foreign Relations, the Senate included the following declaration in its resolution approving Montenegro's accession:
The advice and consent of the Senate under section 1 is subject to the following declarations: … (6) Support for 2014 wales summit defense spending benchmark. The Senate declares that all NATO members should continue to move towards the guideline outlined in the 2014 Wales Summit Declaration to spend a minimum of 2 percent of their Gross Domestic Product (GDP) on defense and 20 percent of their defense budgets on major equipment, including research and development, by 2024.Footnote 49
Several Republican senators likewise emphasized defense spending in their individual statements surrounding the vote on Montenegro.Footnote 50
President Trump signed the U.S. instrument of ratification of the accession protocol on April 11—the day before Trump announced his change of view regarding NATO's obsolescence.Footnote 51 Montenegro became NATO's twenty-ninth member state on June 5, 2017, at a ceremony that took place at the U.S. State Department.Footnote 52
