Fighting back, Democratic Senator Kerry called President Bush “unfit to lead this nation” because of the war in Iraq and his record on jobs, health care, and energy prices. He lashed out at the incumbent and Vice President Cheney for avoiding service in the Vietnam War.

“I’m not going to have my commitment to defend this country questioned by those who refused to serve when they could have and by those who have misled the nation into Iraq,” Mr. Kerry said in prepared remarks issued as the Republican president was poised to accept his party’s nomination for a second term.

Mr. Cheney and Senator Miller, a Democrat of Georgia, led a chorus of Republicans who challenged Mr. Kerry’s credentials to be commander in chief, arguing that although they respect his decorated Vietnam War service, his 20-year voting record in the Senate on national security issues made him unfit for the nation’s top job.

Mr. Kerry answered his critics with a blistering statement.

“For the past week, they attacked my patriotism and my fitness to serve as commander in chief,” Mr. Kerry said. “Well, here’s my answer.”

Mr. Bush served stateside in the Texas Air National Guard. Mr. Cheney received five deferments and never served in the military.

Earlier yesterday, Mr. Kerry’s running mate, John Edwards, accused Republicans of using their convention to assail Mr. Kerry rather than offer ideas for solving the nation’s most pressing problems.

The GOP spent “all of their time and all of their energy trying to tear down a patriot,” Mr. Edwards told a town-hall audience in the Philadelphia suburb of Norristown, Pa.

“The anger we heard from Senator Miller, the anger we heard from the vice president – anger is not going to change this country and do what needs to be done for America,” Mr. Edwards said.

Where was the “anger and venom” about the millions of Americans who had lost their health insurance or their jobs? he asked.

“It doesn’t surprise me that the vice president of the United States spent most of his speech talking about John Kerry because you know he doesn’t want to talk about what they’ve done to this country,” the North Carolina senator said.

He was traveling to Ohio to join Mr. Kerry at a late-night rally. The campaign appearance was set to begin moments after the Republican convention concluded in New York, part of the Democrats’ effort to trim the GOP’s post-convention momentum.

In his appearance, Mr. Edwards described last month’s Democratic convention in Boston as a positive gathering in which they laid out their agenda and vision for the country. He reminded the audience that just a few years ago Mr. Miller had called Mr. Kerry, a decorated Vietnam War veteran, a patriot.

Mr. Edwards also made the rounds of yesterday’s morning talk shows to respond to the criticism of Mr. Kerry, calling it “completely over the top.”

On CBS’s “The Early Show,” Mr. Edwards mocked Mr. Cheney for saying “the black market network that supplied nuclear weapons technology to Libya, as well as to Iran and North Korea, has been shut down.”

“He said that with a straight face on the same day that the Iranians themselves were declaring that they were moving forward with their nuclear weapons development program,” Mr. Edwards said.