Her statement, lengthy and somewhat defensive, allowed, “While the rules of political expediency would say I should have refused to meet with President-elect Trump, I never have and never will play politics with American and Syrian lives.”

She then made the case against any intervention in a war that has pulled in Russia and left hundreds of thousands slaughtered.

“President-elect Trump and I had a frank and positive conversation in which we discussed a variety of foreign policy issues in depth. I shared with him my grave concerns that escalating the war in Syria by implementing a so-called no-fly/safe zone would be disastrous for the Syrian people, our country and the world. It would lead to more death and suffering, exacerbate the refugee crisis, strengthen ISIS and Al Qaeda, and bring us into a direct conflict with Russia, which could result in a nuclear war. We discussed my bill to end our country’s illegal war to overthrow the Syrian government, and the need to focus our precious resources on rebuilding our own country, and on defeating Al Qaeda, ISIS and other terrorist groups who pose a threat to the American people.”

Her case is a break from the position that her fellow Democrat, Hillary Clinton, campaigned on. It fits nicely with Mr. Trump’s reluctance to engage — and with warnings against American involvement from the president of Russia, Vladimir V. Putin.

Kellyanne Conway advises Democrats on ‘identity politics.’

And speaking of Ms. Gabbard, Kellyanne Conway, a Trump senior adviser and his campaign manager, took some time on Monday to laud the fledgling rebellion in Democratic ranks against the liberal old guard.

Speaking to reporters, Ms. Conway praised Ms. Gabbard’s willingness to buck the party, boosted Representative Tim Ryan, a Democrat from Youngstown, Ohio, who is challenging Representative Nancy Pelosi’s leadership, and had kind words for Senator Bernie Sanders of Vermont, who has said Democrats need to focus more on economic struggles and less on the grievances of minorities and women.

“Bernie Sanders today was also quoted as saying they should stop identity politics in the Democratic Party. Whoa. He can call and we’ll tell him how to do that and win,” she said.

Mr. Sanders struck back in his way, declaring the Trump infrastructure a scam for fat-cat investors.