Hatch spent Friday and Saturday in the country, visiting a market in Ramadi, chatting with about a dozen Utah soldiers, and meeting officials from the Iraqi government and U.S. military in Baghdad.

"In all, the change I witnessed since I went to Iraq last year is substantial," Hatch said. "I believe we've made headway. That's not to say victory will be achieved tomorrow. It's going to take quite a while."

A year ago, he said, going to a market in Ramadi was unthinkable because of the violence.

When he visited, he was shuttled in an armored vehicle with military escorts, wearing body armor and helmet, but he said he saw shopkeepers selling their goods and high-fived eager Iraqi children.

"The situation today is remarkably improved. Three months ago you couldn't walk down the streets of Ramadi without being attacked," he said.

The following day, a truck containing chlorine gas exploded in Ramadi. Reports of the number of casualties varied from two to 11, with dozens injured.

Hatch said the surge strategy - the deployment of more than 20,000 new troops in a more assertive role - espoused by President Bush and Gen. David Petraeus - has allowed the United States to restore order and control in neighborhoods.

It has also led to an increase in the rate of U.S. casualties. An average of 3.2 coalition soldiers have been killed each day since Feb. 1, according to statistics compiled by the Web site Iraq Coalition Casualty Count. Since the war began, the average had been 2.4 per day.

"There's good reason for that. They're actually going into Baghdad and taking them on," Hatch said. "Nobody wants to see our young men and women become casualties, but the fact of the matter is we're trying to stop a worldwide movement of al-Qaida and their sympathizers. Can you imagine what would happen if they get their hands on weapons of mass destruction?"

But Jon Soltz, an Iraq veteran and founder of the group VoteVets.org, said Hatch's view of Iraq is "incredibly myopic and mostly smoke and mirrors."

"What is happening is what we call the 'amoeba effect.' That is, insurgents and terrorists go where you aren't," he said. "That's why there's been no real drop off in sectarian violence across Iraq as a whole, and why, unless you're willing and able to put half a million Americans in Iraq for 10 years, there's no solely military solution."

Hatch was in Iraq with Sen. Gordon Smith, R-Ore., and Rep. Jane Harman, D-Calif., two members of Congress who have been critical of the conduct of the war.

They met with Iraqi Prime Minister Nouri al-Maliki and other government leaders and urged them to make major reforms, including an agreement on oil revenue sharing among the country's regions and changes to its constitution.

Smith's assessment was less optimistic than Hatch's.

Iraqi political leaders "are in gridlock," Smith told The Associated Press. "They are focused more on revenge than on reconciliation."

Hatch acknowledged difficulties ahead.

"Optimism is one thing. There's nothing easy about this. I came away knowing there's still a lot of heavy lifting over there," said the Utah Republican.

"[But] I came back from this trip with a more positive view of the overall situation."