DES MOINES, Iowa (AP) — The Latest on the January Democratic presidential debate (all times local):

8:55 p.m.

What has become a signature trade deal of President Donald Trump's administration is a conflict point among the Democrats competing to replace him.

Vermont Sen. Bernie Sanders said at Tuesday night's Democratic presidential debate at Drake University in Des Moines, Iowa, that he opposes the United States-Mexico-Canada trade agreement, or USMCA, in part because it "does not incorporate very, very strong principles to significantly lower fossil fuel emissions in the world."

Asked why she backed the deal, Massachusetts Sen. Elizabeth Warren said it was a "modest improvement" over existing agreements and could be a placeholder for future reform.

Former Vice President Joe Biden said that, as president, he wouldn't push a trade deal that didn't include buy-in from environmentalists and unionists. Minnesota Sen. Amy Klobuchar said she backed the deal, as did former South Bend, Indiana, Mayor Pete Buttigieg, who said it “has been improved. It is not perfect.”

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8:35 p.m.

There’s a divide in Tuesday night’s Democratic presidential debate over the American military footprint abroad.

The leading progressive candidates, Sens. Elizabeth Warren and Bernie Sanders, blasted the trillions of dollars that the U.S. has spent in Middle East wars since the Sept. 11 terror attacks. Warren said “We have to stop this mindset” and bring home “combat troops.”

The more moderate candidates countered that a U.S. presence is necessary in the Middle East, though former Vice President Joe Biden, Sen. Amy Klobuchar and former Mayor Pete Buttigieg said the focus should be on small special forces.

To some degree, the debate is about framing. Sanders and Warren don’t go so far as to say they would never order military deployments. Biden, Klobuchar and Buttigieg are careful to express caution about large, extended missions of ground troops.

But the differences highlight two distinct foreign policy camps within the Democratic Party.

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8:25 p.m.

Democratic presidential hopeful Bernie Sanders says he fears that President Donald Trump's actions involving Iran could be leading the United States into a foreign policy quagmire of the highest level.

The Vermont senator said at Tuesday night's Democratic candidate debate at Drake University in Des Moines, Iowa, that what he sees as the country's top foreign policy disasters - the wars in Vietnam and Iraq - were “based on lies.”

Sanders accused Trump of being dishonest about the intelligence that led to the U.S. airstrike that killed Iranian Gen. Qassem Soleimani. Sanders pressed the need for an international coalition, adding, "We cannot keep acting unilaterally."

Defense Secretary Mark Esper said this week that he had seen no hard evidence that four American embassies had been under threat when Trump authorized the targeting of Iran’s top commander, raising questions about the scale of the threat described by Trump last week.

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8:15 p.m.

Former Vice President Joe Biden wasted no time in the opening minutes of Democrats’ presidential debate in calling his 2002 vote authorizing an Iraq invasion a mistake.

It was an unusually matter-of-fact tone of contrition for Biden, especially as he tries to emphasize his long foreign policy record as a vice president and a six-term U.S. senator. The 77-year-old candidate has throughout his campaign mostly defended portions of his record that have come under criticism from his party’s progressive flank.

Vermont Sen. Bernie Sanders nonetheless tried to capitalize on the issue Tuesday night. He pointed out that he voted against the Bush administration’s war powers request as a member of the House, and he called the war the “worst foreign policy blunder in history.”

Biden maintained that he’d compare his “record overall” to any of his Democratic competitors, and he pointed to his role in the Obama administration in dramatically scaling back U.S. involvement in Iraq.

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8 p.m.

Six Democratic presidential candidates are taking the debate stage in Des Moines, Iowa, in a final showdown before primary voting begins.

The half dozen candidates on stage Tuesday are all white and include four men. It's a stark winnowing of the Democratic field that was once the most diverse in history.

The first debate of 2020 is starting with fresh tension between Vermont Sen. Bernie Sanders and Massachusetts Sen. Elizabeth Warren. Warren said Monday night that Sanders privately told her in 2018 that he didn’t think a woman could defeat President Donald Trump. Sanders has vigorously denied making the comment.

The dispute isn’t likely to be the only one on stage. Sanders has ratcheted up his criticism of Vice President Joe Biden over his past support of the Iraq War and other issues. Minnesota Sen. Amy Klobuchar is looking to break out of the pack, building on strong debates and her arguments that former South Bend, Indiana, Mayor Pete Buttigieg doesn’t have enough experience to be president. Billionaire Tom Steyer is expected to face criticism that he's trying to buy his way to the White House as he floods early voting states with campaign ads.

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