Editor's Note: This article is one of 50 in a series about Trump's first two years as president.

At his first Cabinet meeting of the year—not long after the secretary of defense had resigned, protesting the president’s attitudes about America’s allies—President Donald Trump revisited a pet peeve of his. The United States had been, he said, “taken advantage of by so many countries on our military,” and he focused in particular on Afghanistan.

Previous presidents have been humbled that the first-ever invocation of NATO’s mutual-defense clause was to protect the United States after the September 11 attacks, and viewed the common undertaking in Afghanistan as proof of allied solidarity. The current leader of the free world, however, does not credit allies for shedding their blood alongside Americans in Afghanistan these past 19 years. Instead, Trump said: “I’ve heard past presidents, ‘Well, they’re involved in the Afghanistan war because they sent us 100 soldiers.’  And yet, it’s costing us billions and billions of dollars.”

America’s leadership of the international order is of a type unique for a dominant power: Previous superpowers had to force countries into compliance; the U.S. instead designed an international order. Successive American governments largely played defense of liberal states and incentivized transitions to democracy, but rarely coerced compliance. As Dwight Eisenhower described the strategy, military force would be used to deter predation by the Soviets, while the magnetism of America’s freedoms and prosperity lured states into cooperation. And it worked, keeping the United States and its allies prosperous and largely safe for the past 70 years.

President Trump doesn’t agree with either tenet of that strategy, though.

He doesn’t believe the Soviets were predatory, as illustrated by his bizarre explanation that they were justified in invading Afghanistan. “The reason Russia was in Afghanistan was because terrorists were going into Russia,” the president said. “They were right to be there.” (The Wall Street Journal castigated the president for that, editorializing, “We cannot recall a more absurd misstatement of history by an American President.”)

Trump also doesn’t appear to believe that allied participation has any substantive or symbolic value. “What other countries have done for the last long period of time is give us some soldiers and then talk about it like it’s the end of the world, and we’re subsidizing their militaries by billions and billions and billions of dollars,” he said this month. Previous presidents believed that having allies voluntarily join in was validating, reinforcing the justness of our decisions to use military force; Trump is flatly transactional.

The problem with that approach is that it is penny-wise and pound-foolish. The president can force allies to pay more this time, but it makes those same allies less likely to contribute to future efforts. He may say “We never let anybody down,” but that statement is true only if allies say it, not if we say it of ourselves. And because Trump has violated the norms of America’s alliance relations, our allies are unlikely to agree.

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