A year after he sent troops to Iraq, President Bush (search) is thanking about 20,000 who have returned to a military base in Kentucky and meeting with survivors of some who never made it home.

The trip Thursday to Fort Campbell (search) is part of Bush's campaign to persuade Americans to give him another four years as commander in chief, at a time when military leadership occupies center stage in the presidential campaign.

Democrat John Kerry accuses Bush of leaving American troops vulnerable in Iraq, while Bush and Vice President Dick Cheney (search) argue that Kerry lacks the judgment to lead the armed forces.

Bush last visited Fort Campbell on Nov. 21, 2001, about two months after the terrorist attacks in New York and Washington. Then, Bush's aim was to rally the troops. On Thursday, the eve of the one-year anniversary of the U.S.-led invasion of Iraq, his intention was to give thanks and to place his political strong suit — national security — on full display.

By a 2-to-1 margin, polls show that voters approve of the way Bush is handling terrorism. However, those surveys suggest the public remains divided about the Iraq war.

Fort Campbell has the third-largest military population in the Army. It also has lost the most soldiers in the Iraq campaign: Of the 564 U.S. servicemembers who have died in Iraq, 60 have been from Fort Campbell. Hundreds have been injured.

After his remarks to the troops, Bush and first lady Laura Bush were to eat lunch with the soldiers and meet with some of their relatives.

The president wanted to "express his gratitude on behalf of the nation to our troops and their families for their service and sacrifice," White House spokesman Scott McClellan said. "Our troops are defending our freedoms in the war on terrorism, and they're helping to make the world a safer place and to make America more secure."

Bush and Kerry are both working hard to try to polish their military-leadership credentials, and raise questions about each other's fitness to be commander in chief.

Vice President Dick Cheney, speaking Wednesday in California, praised Bush's victories in the war on terror and portrayed his boss as a strong, decisive leader — characteristics required for a wartime president and ones, he argued, that Kerry lacks. Cheney devoted much of his speech to criticizing the Massachusetts senator, citing Kerry's votes against weapons and defense spending, and his opposing stands on Iraq. Kerry opposed the 1991 Persian Gulf War to oust Iraq from Kuwait but supported giving Bush congressional authorization for the current U.S. campaign in Iraq.

"Whatever the explanation ... it is not an impressive record for someone who aspires to become commander in chief in this time of testing for our country," Cheney said. "Senator Kerry has been one vote of 100 in the United States Senate and fortunately on matters of national security he was very often in the minority."

Flanked by defense officials and diplomats from the Clinton administration, Kerry delivered a broadside to Bush's strategy for Iraq, focusing on the unending hostilities, alienated allies and the loss of lives. As the presumptive Democratic presidential nominee spoke in Washington, a deadly explosion at a Baghdad hotel served as a stark reminder of the perils in postwar Iraq.

"Today we know that the mission is not finished, hostilities have not ended, and our men and women in uniform fight on almost alone with the target squarely on their backs," Kerry said. "Every day they face danger and death from suicide bombers, roadside bombers, and now, ironically, from the very Iraqi police they are training."