During the campaign, President Donald Trump regularly blasted America’s allies for taking advantage of Washington. He invoked the failure of many NATO members to meet their defense-spending targets and suggested that the United States should allow South Korea and Japan to go nuclear rather than continue to rely on American security guarantees. He generally argued that our allies gain a competitive economic advantage by shifting their defense burdens onto the United States.

In his “American Carnage” inaugural address, Trump continued this theme: “For many decades,” he said, “we've enriched foreign industry at the expense of American industry — subsidized the armies of other countries, while allowing for the very sad depletion of our military.” This week, Defense Secretary Jim Mattis reiterated this basic stance, telling NATO members they would need to meet their budget targets or “see America moderate its commitment to this alliance.”

That is an astonishingly misguided position. The “fairness” argument that undergirds Trump’s appeals disregards a fundamental point of American foreign policy: The under-provision of defense by allies is not a bug in America’s global security architecture. It’s a feature.

We’ve heard this argument before, though rarely in such extreme form

The argument for “burden sharing” — that American allies, who are much richer in both absolute and relative terms than when the United States established the current global security architecture, should pay a larger share for their own defense — is far from new. During the primaries, Bernie Sanders called for American allies to do more, and Hilary Clinton pledged to work with NATO partners to get them to meet the 2 percent of GDP spending targets affirmed at a 2014 NATO summit in Wales. (In fact, there is considerable variation on how much NATO members spend on defense. Some, including Greece, Estonia, and Poland, easily meet the target. Others — such as Hungary, Canada, or Slovenia — spend closer to 1 percent of GDP.)

But the Trump administration’s statements and dispositions seem to go further than previous calls for burden sharing. Many allies — especially those on the front line with Russia, like the Baltic States and Poland — are extremely worried that Trump intends to in effect abandon long-standing commitments.

Why are our allies so concerned? Trump’s calls for burden sharing come in the context of an “America First” agenda — itself the rallying cry of isolationists during the Second World War. And the president sees American relationships with other countries as bilateral, short-term, transactional, and zero-sum. What matters is the immediate ledger: how much the United States spends compared to a particular ally on defense, the size of the relevant trade deficit, and so forth.

This worldview has an intuitive appeal, and can appeal to voters. After all, it seems grossly unfair that the United States spent 3.6 percent of its GDP on defense in 2015, while Germany spent around 1.2 percent. And of course, American conventional and nuclear forces help ensure German security.

So is the United States acting like a chump? On an economic level, the costs and benefits of America’s global security guarantees prove rather difficult to calculate. Some scholars argue that, in essence, Trump is correct: America could withdraw much of its overseas military presence, use the savings for tax cuts or investments, and maintain important trading relationships via bilateral means. Others contend that the United States receives positive economic returns from its international commitments.

The value of our defense spending can’t be captured in dollars alone

But to assess American military commitments simply in economic terms misses the point. For the past 60 years, both Democratic and Republican administrations have often worked to foster dependence on the US security architecture. This included actively discouraging independent European military capabilities that would compete with NATO.

The United States enjoys enormous advantages that derive from owning and operating hundreds of military bases spanning the alliance network — many in Germany and Japan. It also benefits from access agreements with many more allies and partners. All of this makes it much easier for the United States to project power globally. The American base in Ramstein, Germany, for example, currently provides a key hub for US Air Force missions in the Middle East that target the Islamic State. (To put the existence of this base in perspective, try to imagine South Korea or Italy operating a major military base in Kansas or Michigan.)

In addition, many of our allies underwrite the basing of US forces on their territory. The US architecture, as a whole, encourages allies to defer spending on their own militaries, while subsidizing US forward operations. (Japan is currently increasing its military capabilities in response to China’s own military buildup, but in ways that presuppose — and even depend upon — incredibly close cooperation with the United States.)

These relationships, including the asymmetric military capabilities and the commitments provided by the United States, add up to security interdependence on Washington’s terms. Dependence on the US constitutes a huge source of strength in the international system. It means that the wealthiest states in the world both need — and cannot challenge — American dominance. Think about it: The United Kingdom, France, Germany, Italy, and Japan are not engaged in great-power rivalries with one another, or with the United States. Instead, they are all part of an American-centric security architecture, in which the United States has muted their desire, and ability, to become military peer-competitors.

In short, this is a terrific deal for America. Only two great powers — Russia and China — stand as potential rivals to the United States. And these potential rivals are currently blocked from alliances with the wealthiest and most scientifically advanced partners in the world, because those countries are closely aligned with the United States. Consider how, in the early 20th century, it made Britain’s defense policy much easier when it ceased having to hedge against military conflict with the United States. Not only does the United States not have to worry about either European powers or some of the strongest Asian states, but it exercises, at least for now, significant influence over their security policies.

If our allies really paid their “fair share,” new military rivalries might emerge

Properly understood, Trump’s call for “America first” promises not American strength, but weakness. Again, there is nothing new about the United States placing pressure on its partners to shoulder slightly more of the defense burden. But coupling those demands to the rest of the “America first” agenda — not to mention Trump’s own mercurial treatment of some of Washington’s most durable partnerships — calls into question the basic bargain that makes our allies willing to accept strategic dependency on the United States. Unequal military power is a part of that bargain.

Trump may extract some concessions — from NATO members, and particularly from Japan and other Asian states worried about China. But since Trump says he wants to increase defense spending regardless of how his bid for burden sharing plays out, it’s even unclear what economic benefit the United States will derive from pressuring its allies.

And when those allies start making major military investments, we should be even more concerned. After all, if Washington cannot be trusted to honor its commitments, or to adopt policies of enlightened self-interest toward its partners, why should our allies tolerate a continued position of vulnerability vis-à-vis the United States?

Trump’s approach to burden-sharing sends the message to our allies that the United States may abandon them as soon as the short-term cost-benefit calculus suggests doing so — such as when defending them risks war, or when the next recession makes bashing “free riding” allies politically expedient. But as Article 5 of the NATO alliance, which pledges collective security, becomes conditional, it becomes more and more irrelevant.

Dangerous hints that allies are weighing options beyond the US

Indeed, there are already signs that our allies are looking into ways to hedge their bets — to explore “exit options” that could allow them to decouple from the American security architecture. In a shocking statement for a German chancellor, Angela Merkel responded to Trump’s rhetoric by saying that Europe’s fate is “in its own hands.” A February 2017 Infratest poll found that only 22 percent of Germans believe that the United States is a trustworthy ally, down from 59 percent in November.

Guy Verhofstadt, the former prime minister of Belgium and current member of the European Parliament, has called for an EU army funded collectively by the member states. “If we don't want to become the object of Trump-Putin deals, we must put into place real EU defence and foreign policy now,” he tweeted in January. Jaroslaw Kaczynski, the head of the nationalist Law and Justice Party in Poland, gave a shocking interview with a German newspaper, in which he called for a European nuclear arsenal that would rival that of Russia — and by extension that of the United States.

At first glance, a more muscular Europe might seem to be exactly what Trump wants. But such decoupling from the US sets in motion a new great-power politics, opening up possibility of new combinations of middle-sized powers that could eventually challenge the American preponderance of power.

There is already talk in Berlin of pursuing closer German-Chinese relations as one way of reducing dependency on Washington. If the state of play continues to worsen, then European states may even begin to question the prudence of allowing American forward basing, including at Ramstein, on their territory.

It’s easy for more powerful states to push weaker ones around — even allies. But real leaders understand the durable power that comes from authority and deference. Yes, many states rely on our security guarantee. And, yes, the United States sometimes pays disproportionately in financial terms. But that’s a small price to pay for global stability.

Abraham Newman is an associate professor in the Edmund A. Walsh School of Foreign Service and in the department of government at Georgetown University. He is the author of Protectors of Privacy: Regulating Personal Data in the Global Economy. Twitter: @ANewman_forward.

Daniel Nexon is an associate professor in the Edmund A. Walsh School of Foreign Service and in the government department at Georgetown. He blogs at The Duck of Minerva and Lawyers, Guns and Money, and is the author of The Struggle for Power in Early Modern Europe: Religious Conflict, Dynastic Empires, and International Change. Twitter: @dhnexon

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