As U.S. officials engage with the rebel group now in control of Syria, they are mindful of a painful episode in recent U.S. foreign policy whose consequences continue to unfold: the Taliban takeover of Afghanistan.

Three U.S. diplomats met last week in Damascus, Syria’s capital, with leaders of Hayat Tahrir al-Sham, the rebel militia that recently toppled the dictatorship of Bashar al-Assad. Their goal was to persuade the militant group — the successor to an affiliate of Al Qaeda — to govern the country with an inclusive and moderate hand.

That is the best hope, U.S. officials believe, for preventing Syria from descending into fresh violence and chaos that could further destabilize the Middle East and empower anti-American terrorist groups.

So far, U.S. officials think that the rebels are saying the right things.

The senior State Department official for the Middle East, Barbara Leaf, said the group’s battle-tested leader, Ahmed al-Shara, “came across as pragmatic” in the meeting in Damascus. Mr. al-Shara had offered “moderate statements” on a range of matters, including the rights of women and minority groups, and given assurances that terrorist groups would not operate within Syria, she said.

Even so, U.S. officials remain wary of Mr. al-Shara. They fear he might be sweet-talking to win international backing as he plots to consolidate power and perhaps impose strict Islamic rule, much as Taliban leaders did in 2021 in Afghanistan.