American soldiers are seen at the U.S. Army base in Qayyara, south of Mosul, on October 25, 2016.Alaa Al-Marjani / Reuters

It’s the question that has plagued Democratic politicians since the disaster of the Iraq War: Where does the party stand on the use of U.S. force abroad?

Another way to put it, as the CNN moderator Jake Tapper did when posing the first national-security question of last night’s debate: Should America be the world’s policeman?

Senator Bernie Sanders had a fast answer: No.

That’s easy enough to say. Even Sanders’s centrist rivals, such as Joe Biden, tend to avoid the “world’s policeman” phrase and the idea of an America meddling in endless global conflicts. But from there, Sanders outlined some of the changes he would make. He’d end the war in Afghanistan. He’d shrink America’s massive defense budget. He’d seek to move on from the so-called War on Terror.

It was a quick way of saying that, militarily at least, he’d disengage. And that suggests the conundrum that prompted the question in the first place: Pitching voters on a strategy of U.S. retrenchment can start to sound like echoes of Donald Trump.

To be sure, Trump’s actions as president have raised the likelihood of military conflict with Iran, seen America meddle openly in Venezuela, and seen U.S. troops remain deployed in Afghanistan, Iraq, and, despite the president’s calls for a troop withdrawal, even Syria.

And in his appeals for the use of diplomacy, respect for the United Nations, and a hope to “bring countries together in the Middle East and all over the world,” Sanders sounded decidedly un-Trumpian.

Yet the Democratic candidates, in discussing U.S. engagement overseas, often express the kind of overreliance on talking points and aversion to nuance that have been a hallmark of Trump’s rhetoric on foreign policy—and, like Trump, they risk putting forward a vision for the U.S. role in the world that says more about what it won’t be than about what it will be.

Elizabeth Warren offered a sensible, if vague, mantra: “We should not be asking our military to take on jobs that do not have a military solution. We need to use our diplomatic tools, our economic tools, and if we’re going to send someone into war, we better have a plan for how we are going to get them out on the other end.”

It’s one thing to say that as commander in chief, they’ll bring U.S. troops home—but it’s another to grapple with the fact that ISIS is still a threat in Iraq and Syria, and that tens of thousands of local soldiers who have cast their lot with the U.S. cause are still caught in a dangerous limbo. The debate format may not be ideal for this, and despite the litany of U.S. military engagements overseas and the thousands of U.S. service members deployed in them, the topic came up only briefly, after more than two hours of discussion on mostly domestic issues. But even when giving their own lengthy foreign-policy addresses, the major candidates have largely avoided going into the specifics, such as addressing what a U.S. withdrawal in these places would look like, or grappling with what the repercussions might be not just for America, but also for local civilians and U.S. allies.

John Hickenlooper, who is polling near the bottom of the field, outlined some of these concerns in his own remarks about Afghanistan. “If we completely pull our troops out of there, you’re going to see a humanitarian disaster that will startle and frighten every man, woman, and child in this country,” he said. “We’re going to turn our backs and walk away from people that risked their lives to help them build a different future?”

In his own short remarks, Beto O’Rourke promised to end U.S. military engagements not just in Afghanistan, but also in Iraq, Syria, Yemen, Somalia, and Libya, while promising not to start any new wars. (Trump repeatedly expresses his aversion to foreign interventions.)

Pete Buttigieg was more measured. While vowing to pull out U.S. troops from Afghanistan by the end of his first year in office, he also said that “around the world, we will do whatever it takes to keep America safe,” keeping with the more centrist vision he attempted to put forward in his own foreign-policy speech. Buttigieg, who served in Afghanistan as a Navy reservist, also offered a concrete proposal: that any congressional authorization of military force would need to be renewed every three years—which would perhaps do more than anything the other candidates said to end what he termed “endless” wars.

U.S. presidents from George W. Bush to Trump have justified U.S. military engagements around the world based on the authorization that Bush received from Congress in 2001 to fight al-Qaeda and any “associated forces.” Buttigieg’s proposal wouldn’t limit the president’s ability to launch military strikes in the name of self-defense.

Still, even these small specifics at least encourage a better debate—and Democrats need to have one if they are to put together a coherent vision on foreign policy to compete with the easy sound bites of Trump’s America First approach.

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