Aspen, Colo. — For 32 years, a group of Republican and Democratic foreign-policy experts has gathered here each summer to debate strategic issues facing the country. This year the bipartisan group had a strange imbalance: None of the Republicans was prepared to argue the case of the GOP nominee, Donald Trump.

Trump would probably be pleased to know that he failed to muster support from the Aspen Strategy Group, as this gathering is known. In a sense, he’s running against the elite foreign policy establishment that the group represents. He is happy to lose the Aspen primary if that strengthens his populist appeal in November.

Trump’s shadow hung over this week’s meeting here. Fifteen prominent Republicans who had served in past GOP administrations met Sunday for a private soul-searching session that one attendee described as “painful and empathetic.” The next day, eight of them joined in signing the public declaration by 50 top GOP former national-security officials warning that Trump would be “the most reckless president” in U.S. history.

“We’re seeing a mass exodus of senior and experienced Republicans from Trump on national security. They are deserting him because he has denigrated NATO, appeased (Russian President Vladimir) Putin and shown little faith in American power,” argued Nicholas Burns, director of the Aspen Strategy Group, who served as undersecretary of state under President George W. Bush. Burns had earlier announced that he would support Hillary Clinton for president.

Trump seemed to relish this defection by the establishment. He described the 50 signers of the declaration as “nothing more than the failed Washington elite looking to hold onto their power,” and thanked them “for coming forward so everyone in the country knows who deserves the blame for making the world such a dangerous place.”

What does the foreign policy elite discuss in a time of anti-elitism? Partly, this year’s Aspen gathering (of which I’m a member, along with several other journalists) explored why experts had missed early warnings of public anger over trade and immigration that have fueled Trump.

But the conversation focused mostly on the technical details of strategic planning: How should the National Security Council staff be organized to give better foresight and efficiency? How can U.S. technology be leveraged to deter Russia and China? A convention of machinists likes to talk about its tools; so too with this collection of experts.

What’s unusual about the Aspen group is that in a time of deep political polarization, it struggles for bipartisan consensus. Explains Peter Feaver, a Duke professor who served on Bush’s NSC staff: “Principled disagreement of the sort that happens in the ASG opens the door to both pragmatic compromise … and persuasion, where you actually learn from the other side.” However elitist this may sound, such a consensus-building process is part of what makes American democracy work.

Stephen Hadley, who served as national security adviser during Bush’s second term, is a prime example of quiet, principled, bipartisan public service. He didn’t sign the letter denouncing Trump, and he cautioned me here that foreign policy experts should pay careful attention to the growing public anger that “globalization was a mistake” and that “the elites have sleep-walked the country into danger.”

“This election isn’t just about Donald Trump,” Hadley argued. “It’s about the discontents of our democracy, and how we are going to address them. The genius of our political system is that these discontents are being worked out this year within our political parties. Whoever is elected will have to deal with these discontents. If not, the anger against the system may be played out next time in the streets, as in the 1960s.”

Philip Zelikow, a University of Virginia professor who also served in the Bush State Department, argues that the global engagement Trump resists can be summed up in two simple sentences: “The future of America depends on partners and friends in the world. The future of America depends on doing business in the world.” Most Americans, even Trump supporters, would endorse these principles if they could be articulated more clearly, he says.

With Trump running so hard against the traditional foreign policy consensus, there’s an unusual opportunity for Clinton to rebuild this framework in a way that speaks to the voters’ discontent — and also reweaves the narrative of American power for the 21st century.

Prominent Republicans are helping Clinton make her argument. But she has to make the case that updated global engagement on trade, security and economic issues as discussed by this group of professors and diplomats in a pristine mountain resort will benefit the average citizen.

— David Ignatius is a columnist for Washington Post Writers Group.