Nashville, Tenn. ? In his most pointed attempt yet to distinguish his stand on the war from President Bush’s, Sen. John Kerry said Wednesday that “extremism has gained momentum” and the world is more dangerous because of the Bush administration’s bungling in Iraq.

Speaking to about 5,000 American Legion members at their annual convention, Kerry listed a series of bad decisions by the “civilian leadership” that he said left Iraq’s borders unsecured, its security forces untrained and overmatched and its streets in chaos.

“As a result, today terrorists have secured havens in Iraq that were not there before,” Kerry said. “We have been forced to reach accommodation with those who have repeatedly attacked our troops. Violence has spread in Iraq; Iran has expanded its influence.”

While the Democratic presidential candidate was greeted with a standing ovation when he arrived, and the crowd applauded as he spoke of the need to increase funding for veterans’ benefits, the room was silent when he criticized the president. Many in the audience folded their arms across their chests.

Kerry was seeking to regain political momentum after a miserable month. His approval ratings have dropped amid harsh attacks on his Vietnam service record by a Republican-funded veterans group.

Responding two days after a TV interview in which Bush suggested that the war on terrorism couldn’t be won, Kerry said he disagreed. “There’s nothing we can’t do if we put our mind and muscle into it,” he said. “In the end, the terrorists will lose, and we will win because the future does not belong to fear, it belongs to freedom.”

Bush backtracked the next day, insisting that “we are winning and we will win.” White House aides said that in his initial remarks, the president meant only that the war wouldn’t be concluded in the same way conventional wars have been, such as with a surrender ceremony.

Many Democrats are growing anxious that the Kerry campaign has stalled and are urging the candidate to shake things up and adopt a harder edge. Kerry announced some new communications advisers Tuesday night, but campaign aides deny that a shake-up is in the works.

Former Sen. John Glenn, D-Ohio, right, gives the thumbs up to Democratic presidential candidate John Kerry. Kerry addressed members of The American Legion on Wednesday during their national conference in Nashville, Tenn.

Kerry hurt his ability to attack Bush’s handling of the war in early August when he said that he still would’ve voted to give the president authority to invade Iraq even if he had known that weapons of mass destruction wouldn’t be found there.

On Wednesday, Kerry sought to highlight his differences with Bush, saying he would have allowed U.N. inspections to continue in order to build international consensus before invading. In addition, he said he would have brought in more allies and developed a better plan for the postwar period.

Kerry also said it was a mistake to divert resources from Afghanistan, where al-Qaida leader Osama bin Laden has eluded capture.

“So when the president says we have the same position on Iraq, I have to respectfully disagree,” Kerry said. “Our differences could not be plainer. And I have set them out consistently. When it comes to Iraq, it’s not that I would have done one thing different, I would’ve done almost everything differently.”