"Nobody wants to bring troops home more than those of us who have fought in foreign wars," Kerry said. "But it needs to be done at the right time and in a sensible way. This is not that time or that way."
Mr. Bush announced his plan to bring home troops from Cold War-era bases in Europe and Asia on Monday before an earlier session of the same gathering of 15,000 members of the VFW. The president said the repositioning of forces would help save money on maintaining bases overseas.
Kerry singled out for criticism Mr. Bush's plan to cut 12,000 of the 37,000 U.S. troops in South Korea.
"Why are we withdrawing unilaterally 12,000 troops from the Korean Peninsula at the very time we are negotiating with North Korea — a country that really has nuclear weapons?" Kerry asked.
Kerry quoted Republican Sen. John McCain of Arizona as saying that North Korea is probably more dangerous than since the end of the Korean War in 1953. "This is clearly the wrong signal to send at the wrong time," Kerry said.
Kerry argued that Mr. Bush's policy would dangerously reduce forces at a time when the nation is fighting the al Qaeda terrorist network in 60 countries across the globe.
"Let's be clear — the president's vaguely stated plan does not strengthen our hand in the war on terror," he said. "It in no way relieves the strain on our overextended military personnel. It doesn't even begin until 2006 and it takes 10 years to achieve. And this hastily announced plan raises more doubts about our intentions and our commitments than it provides real answers."
A White House spokesman said Kerry's criticism shows a lack of understanding about the new threats the U.S. faces, reports CBS News Correspondent Mark Knoller.
"It shows a 20th century Cold War way of thinking that someone would make such comments," said spokesman Scott McClellan aboard Air Force One. He said President Bush was realigning American forces to deal with terrorism, weapons of mass destruction and rogue states.
Kerry received a polite if not overwhelmingly positive reaction from the VFW. Large portions of the crowd applauded with each promise to protect veteran's benefits and with many points he made about Iraq and terrorism. But there was a clear divide, with scores of veterans sitting with their arms folded while others clapped. One man heckled Kerry, calling him a liar, as VFW sergeants at arms admonished him.
"I'll say it myself. He's a liar," said John Ranson of Fort Thomas, Ky., a 57-year-old Vietnam War veteran who sat a few feet away from the heckler. He said Kerry has not supported U.S. troops as senator or as a Vietnam veteran who protested the war.
But there was no shortage of Kerry supporters, including some who voted for Mr. Bush in 2000. "He's got a mess overseas," Dale Hall, 49, of Franklin Park, Ill., said of Mr. Bush. "I stand behind the troops, of course, but he's not done a good job."
With voters focused on the war on terror, the VFW convention was the perfect backdrop for both candidates to tout their war plans. The convention was set in Ohio, a top battleground state, with a live audience targeted by both campaigns.
Besides describing his redeployment plan, Mr. Bush used his appearance before the veterans to criticize Kerry for saying he plans to reduce the number of U.S. troops in Iraq during his first six months in office.
Although veterans lean Republican, Kerry also is seeking their support in this election. Kerry touts his own service in the Vietnam War as a mutual connection and is even bucking the tradition of suspending campaigning during the opposing party's national convention to speak to the American Legion.
Kerry plans to speak to the group at their convention in Nashville on Sept. 1, in the middle of the Republican National Convention. Kerry spokeswoman Allison Dobson said it's the only event he has scheduled during the GOP gathering in New York City.
Meanwhile, Mr. Bush was riding his campaign bus through the Midwest swing states of Wisconsin and Minnesota on Wednesday.
In Chippewa Falls, Wis., Mr. Bush said he will push for extra education benefits for National Guard members and reservists. Men and women who have "put their jobs on hold" to serve their nation deserve support in return, he told hundreds of supporters.
He said he would increase monthly education benefits for National Guard members and reservists who have been on active duty for more than 90 consecutive days.
Mr. Bush was scheduled to speak later at a rally in St. Paul, Minn., before heading south for a week at his ranch in Crawford, Texas.