In March, Eliot A. Cohen, director of the Strategic Studies Program at Johns Hopkins University’s School of Advanced International Studies, and a former senior State Department counselor for the George W. Bush administration, famously helped organize a “Never Trump” letter, eventually signed by more than 120 former Republican foreign policy and national security officials and experts. Cohen explained that Trump does possess some core views—just not enough of them to give Americans a clear picture of his foreign-policy dispositions. Trump is not a traditional isolationist, although he is wary of what he perceives as lopsided alliance commitments, Cohen noted. Trump believes in a strong military, but is dismissive of past military entanglements. He is pro-Israel, supports Britain’s decision to quit the European Union, and is unusually simpatico with Russian strongman Vladimir Putin. “But none of that amounts to a coherent worldview, which is one of the problems you have in judging a leader who does not read, and feels no need to fundamentally educate himself on the international system that the United States has created over more than half a century,” Cohen said.

But there are important clues to a likely Trump foreign and national security policy embedded in his business career, in the drama of the campaign trail, and in the controversial policy positions he has embraced and frequently discarded. There are also clues in the rapidly expanding circle of advisers and top officials he is now recruiting and appointing, including retired Lieutenant General Michael Flynn as national security adviser; Kansas Representative Mike Pompeo as CIA director; Alabama Senator Jeff Sessions as attorney general; Republican National Committee chairman Reince Priebus as White House chief of staff; and right-wing media mogul and anti-globalist bomb-thrower Steve Bannon as White House chief strategist and senior counselor.

The evidence thus far suggests that Trump is a pragmatist who possesses a mercantilist instinct and boundless confidence in his ability to negotiate trade deals that put “America First.” He is likely to be more aggressive in targeting Islamist terrorist groups such as the Islamic State, and staunching the flow of illegal immigrants. Trump also seems determined to continue stoking the fires of nationalism and aggrieved populism that swept him into office. His approach to allies and adversaries alike will almost certainly be transactional and non-judgmental of authoritarian regimes. Above all, the picture that emerges is of a commander-in-chief untethered from the orthodoxies of the post-World War II, U.S.-constructed liberal international order, suggesting the potential for one of the most disruptive presidencies in modern history.

The Trump Prism

In the personal narrative of ambitious leaders, there is often a formative period or event that crystallizes their view of how the world works. For George H.W. Bush and other members of “The Greatest Generation,” it was the twin horrors of the Great Depression and World War II. Bill Clinton and the Baby Boomers had Vietnam and the 1960s “cultural revolution.” Barack Obama and American millennials have 9/11 and the wars in Iraq and Afghanistan.