Last week’s 10th anniversary of the Iraq War passed quietly, and that’s not a bad thing.

Most Americans have no wish to celebrate the war, fought under false pretenses to a costly and ambiguous end. In Washington last week, however, there were welcome signs that the lessons of Iraq have finally sunk in, among Republicans as well as Democrats.

The mistakes of wars past were on the minds and tongues of the subdued members of the House Foreign Affairs Committee on Wednesday as they questioned administration witnesses. The topic of the hearing wasn’t Iraq but neighboring Syria. Yet the queries, and answers, were those of Americans humbled by Iraq and skeptical about more war.

“It has been said that the U.S. has no good options in Syria, and that’s probably true,” observed the chairman, Ed Royce, R-Calif. “All of it is incredibly unpredictable.”

Rep. Adam Kinzinger, R-Ill., who serves in the Air National Guard, pronounced himself “stumped on the answer in Syria. I’ll be honest, I don’t know what the answer is … I mean, this is a difficult quandary.”

Another Republican, Rep. Doug Collins of Georgia, agreed that there is no “easy postcard answer” in Syria. “I’m afraid we’re going down the same path again that will reap the same problems,” he said. “This is not something we can afford to be playing with the next 10 to 20 years.”

Noteworthy was that Republicans were even more hesitant than Democrats to arm rebels in Syria, where about 70,000 have died and millions have been displaced. Virtually everyone on the committee, however, had questions about the limits of American power — doubts that weren’t in evidence a decade ago.

“Right now we’re looking at the anniversary of Iraq, and a lot of folks are questioning what happened there and why did we do that,” said Rep. Scott Perry, R-Pa. “And it’s topical, because we don’t want to end up there again. And we should learn from those mistakes.” In Syria, he continued, Americans have “no clue what the plan is, and we don’t want the current administration to make the mistakes of any of the past administrations.”

Fielding the most questions for the administration was Robert Ford, ambassador to Syria — a career diplomat who sat hunched over the witness table, hands in lap. In a gentle voice, he offered nonmenacing sentiments such as “ultimately we perceive that a negotiated political transition is the best long-term solution to the Syrian crisis.”

In one stark difference from 2003, Ford and his questioners were skeptical about recent reports that Syria used chemical weapons. Asked what would occur if Syrian President Bashar al-Assad crossed the chemical-weapon “red line,” Ford said only that “there will be consequences.”

“What would those consequences be?” Royce inquired.

“I absolutely do not want to go into hypotheticals,” Ford replied.

Perry, however, invoking the lesson of Iraq, countered that it is important for the public to know about possible actions in advance, because “we don’t want to be in a position of Monday-morning quarterbacking.”

Elsewhere, lawmakers and foreign-policy specialists have advocated direct U.S. military involvement in Syria. But the possibility got scant mention Wednesday, and even the prospect of indirect military support for the opposition worried lawmakers.

“I sincerely do not believe that it is time for the U.S. to arm the rebels,” said Rep. Ileana Ros-Lehtinen, R-Fla., citing al-Qaida’s presence among the rebels.

In general, witness and questioners shared a belief that the United States has limited influence. Royce asked if the United States could “force” the Iraqi government not to allow Iran to ship arms to Syria over and through Iraq.

“We have been very direct with them about … how that is not helpful to Iraqi interests,” was as far as Ford would go.

Rep. Juan Vargas, D-Calif., asked about a trial for Assad. “I don’t think these are decisions that Americans have to make,” Ford answered.

Several lawmakers voiced skepticism about the newly elected leader of the opposition, Ghassan Hitto.

“It just reminds me of (Hamid) Karzai,” said Rep. Karen Bass, D-Calif., referring to the Afghan leader. (Iraqi opposition leader Ahmed Chalabi also comes to mind.) “I mean, (Hitto) hasn’t been in the country for a couple of decades, and he seems pretty weak by everybody’s account.”

Ford offered no defense. “Syrians chose him. We had nothing to do with it,” the ambassador said. “We stayed out of it entirely.”

Dana Milbank is an American political reporter and columnist for The Washington Post. Email to danamilbank@washpost.com.