Ultimately, however, neither Bernie Sanders nor Clinton, whom Murphy endorsed for president, “really represented my views,” Murphy told me, “and I think that there is a big open space in the Democratic Party right now for the articulation of a progressive foreign policy.”

The open question is whether Murphy can fill that space. “I think Donald Trump believes in putting a wall around America and hoping everything turns out OK,” Murphy said in a recent interview. “I believe that the only way that you can protect America is by being forward-deployed [in the world] in a manner that is not just through the point of a spear.”

But where Trump’s “America First” mantra proved a relatively simple and effective sell for voters, Murphy shuns slogans; he repeatedly resisted when I asked him to encapsulate his worldview. The tensions in his vision go beyond the fact that he uses hawkish language like “forward-deployed” to advocate for dovish policies. His central argument is for a dramatic de-emphasis on military power in U.S. foreign policy, and yet he won’t entertain the thought of cutting the defense budget. (As Madeleine Albright would say, “What’s the point of having this superb military if we can’t use it?”) He’s urging Democrats to stake out a winning position on foreign policy … by taking the opposite approach to the guy who just won the last presidential election by promising “simple” solutions and tough measures against “bad dudes.”

“There are no easy answers anymore,” Murphy said. “The bad guys are super-shadowy or are sometimes not the bad guys. One day China’s a bad guy, one day they’re an indispensable economic partner. One day Russia’s our enemy, the next day we’re sitting on the same side of the negotiating table with them. That makes for a really confusing moment.” (Trump’s “America First” platform, it’s worth noting, features its own contradictions and isn’t necessarily coherent itself.) What’s progressive about his philosophy, Murphy explained, “is that it’s an answer to how we exist in the world with a big footprint that doesn’t repeat the mistakes of the Iraq War.”

“American values don’t begin and end with destroyers and aircraft carriers,” he told me. “American values come by helping countries fight corruption to build stability. American values flow through tackling climate change and building energy independence. American values come through humanitarian assistance whereby we try to stop catastrophes from happening.”

Murphy’s message amounts to a gamble; he’s betting on active U.S. involvement in world affairs at a time when many Americans are wary of that approach and tired of remaking other societies in their image. “I think progressives understand that we are Americans at the same time as we are global citizens,” he said. “We are interested first and foremost in creating peace and prosperity here at home, but we aren’t blind to the fact that injustice anywhere in the world is meaningful, important, and worth thinking about. I felt this moment in which even some Democrats and progressives were maybe thinking about closing doors. And I want to make the case that the progressive movement should be thinking about the world.”