NASHVILLE, Tenn. — Democratic presidential candidate John Kerry, seizing on President Bush's suggestion that victory in the war on terrorism might not be possible, declared Tuesday that "we can, we must and we will win the war on terror."

Kerry told about 1,000 people gathered at a late-night airport rally that he would fight a smarter, more effective war by bringing in help from allies who have been opposed to Bush's military leadership.

Kerry said he has not been watching the Republican National Convention on television this week, but he has been reading coverage of it in the newspaper.

"All they're talking about is the war on terror, which the president yesterday said he doesn't think we can win," Kerry said in his first campaign appearance since the beginning of the convention. "Well, ladies and gentlemen, let me tell you something: We can, we must and we will win the war on terror."

Bush said in an interview aired Monday on NBC's "Today" show that he didn't think the war on terror is winnable. On Tuesday, he told the American Legion that "we may never sit down at a peace table, but make no mistake about it, we are winning and we will win."

Kerry was to address the American Legion, the nation's largest veterans organization, on Wednesday. He planned to use the speech to spell out what he sees as Bush's miscalculations on the war on terror and declare that he has the best plan to win, said Kerry adviser Joe Lockhart.

"When the president admits that he's not confident they can win the war on terror, that's what people in politics call a problem," Lockhart said.

The trip to Nashville has been Kerry's only campaigning during the convention. He has spent the rest of the week meeting with senior advisers and relaxing near his Nantucket vacation home.