A sea of people at a Clearwater park waved American flags and patriotic signs as they listened to Mr. Bush, the president's younger brother, whip up support for the men and women fighting in Iraq.
"Each generation has its defining moments," said Bush. "This generation's legacy is being written now, on the seas and in sands of the Middle East."
The Rally for America was the latest in a series of gatherings across the country inspired by syndicated radio talk show host Glenn Beck, who was seeking a way to counter anti-war demonstrations.
Such anti-war protests were held Saturday in cities around the nation.
In New York City's Harlem neighborhood, several hundred demonstrators rallied to commemorate the nonviolent calls for world peace made by slain civil rights leader Martin Luther King. King was assassinated 35 years ago Friday, on April 4, 1968.
Some in the crowd held signs pointing out that the military is made up of a large number of minorities.
"Our youth joins the armed services to escape poverty," said Charles Barron, a city councilman. "Our youth joined the armed services to get better education, not to be somebody's cannon fodder for oil."
Also among the protesters were several Muslims. "We have no business in this war," Hamzi Latif said. "They say it's not a war against Islam, but to me it is."
Surrounded by a blue wall of police officers, an estimated 1,500 people marched through downtown Chicago to show their opposition to the war.
"Control your horses, control those sticks in your hands," former death row inmate Aaron Patterson urged police in a speech before the march. "Let's march peacefully today."
Patterson was referring to a demonstration two weeks ago when thousands of people created a massive traffic jam on Lake Shore Drive, prompting police to made more than 500 arrests. Department spokesman Pat Camden said there were no arrests Saturday.
In Hartford, Conn., several hundred people stood in a cool drizzle to show their support for the troops.
"People who are against this war just don't get it," said Bob Tomasiewicz of Glastonbury, Conn., who drove to the rally in a pickup truck with "Go Protest in Iraq" painted on back.
"Sept. 11 changed everything," he said. "We have to fight terrorism wherever we find it. Saddam Hussein is a terrorist."
The Enduring Families Walk in Jacksonville, N.C., was billed as a nonpartisan bolstering of the troops, many of whom hail from nearby Camp Lejeune.
"This ain't time to be a Democrat or a Republican," said Chuck Dellasantina, a retired Marine and one of about 1,000 who made the 1½-mile trek. "It's time to get out and support the troops."
A CBS News poll indicates that 78 percent approve of the U.S. taking military action against Iraq; the public's approval of this war has remained constant since the war began.