KANSAS CITY, Mo. — New military tactics in Iraq are working, but the best way to honor American soldiers is “by beginning to bring them home,” Senator Clinton told war veterans yesterday.

Mrs. Clinton, seeking the Democratic nomination for president, praised the work that soldiers have done in Iraq but described the government there as “on vacation,” leaving American troops in the middle of a sectarian war.

Later, the Veterans of Foreign Wars were told by Senator McCain, who is seeking the GOP nomination, that withdrawing from Iraq would be a historic mistake — far worse than previous American missteps in the country.

Mr. McCain said he understands that Americans are “sick and tired” of the war, which he said hasn’t gone well. Still, he said General David Petraeus and other military leaders deserve patience.

General Petraeus, the American commander who will report to Congress on progress in Iraq next month, told the group that in some areas, partnerships between coalition forces and Iraqi soldiers are “quite robust.” He also said that Iraqi losses have been three times those suffered by the American-led coalition.

Mrs. Clinton and Mr. McCain spoke to hundreds of members of the VFW, which is holding its annual convention in Kansas City. Today, Senator Obama and a former Republican senator, Fred Thompson, are to speak. President Bush arrives tomorrow.

The hall where the candidates spoke can seat 6,000 people, and both Mrs. Clinton and Mr. McCain drew about half that for their late-morning speeches. The crowd was mostly friendly to Mrs. Clinton and offered polite applause throughout her speech. Mr. McCain, a former Vietnam War prisoner of war, received a warmer reception — and louder applause during his remarks.

Mrs. Clinton said she wanted to restore America’s image abroad. “People have to root for America,” she said. “They have to want to be on our side.”

In Iraq, she said, the government must take responsibility for itself and its people.

“I do not think the Iraqis are ready to do what they have to do for themselves yet,” she said. “I think it is unacceptable for our troops to be caught in the crossfire of a sectarian civil war while the Iraqi government is on vacation.”

Mrs. Clinton said new tactics have brought some success against insurgents, particularly in Iraq’s Anbar province.

“It’s working. We’re just years too late in changing our tactics,” she said. “We can’t ever let that happen again. We can’t be fighting the last war. We have to keep preparing to fight the new war.”

Mr. McCain said pulling out of Iraq would empower Al Qaeda and Iran and unleash a “full-scale civil war” in Iraq.

He drew applause when he said, “As long as we have a chance to succeed, we must try to succeed.” Later, he said, “We’re starting to succeed, and I think we’re seeing some shift in public opinion.”