He had been called a racist, a bigot, and even a fascist, but it is likely that for the Washington elite no epithet attached to Donald Trump was more meaningful than Hillary Clinton calling him incoherent.

"Americans aren't just electing a President in November," Clinton told a crowd of supporters and military personnel in San Diego in early June. "We're choosing our next commander-in-chief—the person we count on to decide questions of war and peace, life and death."

This was Clinton's first direct and sustained attack on Trump, and though Democrats had been preoccupied with the unsavory identity politics of the presumptive Republican nominee, Clinton devoted only a few lines to calling out Trump's habits of "demonizing Muslims" and insulting women, Mexicans, and the disabled. Most of her speech went after Trump's utterances on foreign policy. "Like many across our country and around the world, I believe the person the Republicans have nominated for President cannot do the job," she said. "Donald Trump's ideas aren't just different—they are dangerously incoherent. They're not even really ideas—just a series of bizarre rants, personal feuds, and outright lies."

Pundits across the Beltway's ideological spectrum cheered. Conservatives at the National Review and Fox News agreed with liberals at Huffington Post and Vox that this was Clinton's "best speech yet" and "her best case against Donald Trump." In recent days she has built the theme of Trump's "dangerous, incoherent" ideas into her stump speech.

What Clinton and her bi-partisan allies find most objectionable in Trump's foreign policy pronouncements is not so much their lack of coherence but their discordance with the idea that America should be the leader of the world. "It's a choice between a fearful America that's less secure and less engaged with the world," Clinton declared, "and a strong, confident America that leads to keep our country safe and our economy growing."

Trump has certainly had his inconsistencies, but "Make America Great Again" has never meant "Make America Lead Again." Clinton singled out for opprobrium the proposals made by Trump that would dismantle a century-long project initiated by progressives to remake other countries in the image of the United States. That project, which historians of U.S. foreign relations typically refer to as Wilsonianism, after the first president to give it intellectual shape, has been carried out with varying degrees of militancy but always embraced uncritically by both Democratic and Republican presidents since Wilson declared the United States to be "the savior of the world."

To Clinton and other inheritors of Wilson's calling, Trump's specific sins are what some have crudely called isolationism. Rather than seek U.S. military dominance as a means to extend American influence, Trump has insisted that other nations bolster their militaries and defend themselves, which Clinton dismissively reduced to a demand to "let more countries have nuclear weapons."

Trump undoubtedly set fire to the hair of every Wilsonian when he called the North Atlantic Treaty Organization (NATO) "obsolete" and a financial burden for the United States and said he would "certainly look at" getting rid of it. As a multilateral but American-led force that has protected U.S.-approved governments in Europe, NATO is quintessentially Wilsonian and near and dear to Clinton, who first championed it when she was First Lady. She was the most enthusiastic advocate among her husband's advisors for a bombing campaign against Serbian forces in the former Yugoslavia, and famously asked, "What do we have NATO for if not to defend our way of life?" Now, she sees a man who "would abandon our allies in NATO," which she considers to be "one of the best investments America has ever made."

What Clinton offers instead of Trump's "truly dangerous path" is a foreign policy built upon the classically Wilsonian idea that America "is an exceptional country" that is the "last, best hope on earth." She promises to "secure American leadership" and to prove, through diplomacy and military action, that "our country represents something special, not just to us, [but] to the world."

Unfortunately, presidents with these coherent ideas have been the most dangerous of all.

Woodrow Wilson, Franklin Roosevelt, Harry Truman, John F. Kennedy, Lyndon Johnson, Richard Nixon, and George W. Bush—the presidents most driven to make the world democratic, capitalist, and amenable to American interests—promoted and oversaw U.S. involvement in wars that killed, by great magnitudes, more Americans and foreign civilians than all the other presidents combined, and whose benefits for ordinary Americans, if any, are still far from clear.

Clinton herself has never seen an opportunity for American military intervention she didn't like. As Secretary of State she was the most enthusiastic of all of Obama's senior civilian advisors about the plan for a surge of troops into Afghanistan in 2009, and in 2011 she led the "humanitarian interventionists" in the administration who persuaded Obama to bomb Libya. In his comprehensive review of her work in the Obama administration, James Traub of Foreign Policy concludes that "at bottom, Clinton was a reflexive advocate of the military."

During her tenure at State, Clinton delivered a speech to the Council on Foreign Relations that was noted by many observers for its frank and unreconstructed Wilsonianism. In it, she declared that American leadership was needed more than ever. "When old adversaries need an honest broker or fundamental freedoms need a champion, people turn to us," she said. "When the earth shakes or rivers overflow their banks, when pandemics rage or simmering tensions burst into violence, the world looks to us." She claimed that she saw "on the faces of the people I meet as I travel" a desire for America "not just to engage, but to lead." The whole world, she said, "looks to us because America has the reach and resolve to mobilize the shared effort needed to solve problems on a global scale, in defense of our own interests but also as a force for progress." For the United States, "global leadership is both a responsibility and an unparalleled opportunity."

But as we are likely to find out under President Clinton, global leadership can also get a lot of people killed.