The former Iraqi president was found guilty of crimes against humanity and sentenced to hang by a US-sponsored court in Baghdad on Sunday. Bush did not directly address the death sentence that has been assailed by Washington's close European allies.
The verdict came two days before US congressional elections in which Bush's Republicans are at risk of losing control of the House of Representatives and the Senate. Democrats have tried to make the election a referendum on Bush's handling of the Iraq war.
"Saddam Hussein's trial is a milestone in the Iraqi people's effort to replace the rule of a tyrant with the rule of law," Bush said.
"It is a major achievement for Iraq's young democracy and its constitutional government," he said.
Republicans seized on the conviction and sentencing as evidence of progress in Iraq, and White House spokesman Tony Snow called it "a good day for the Iraqi people."
But election-season bickering quickly broke out. Democrats said justice was served but that it was unclear how the verdict would change the course of the war.
"The Iraqis have traded a dictator for chaos. Neither option is acceptable, especially when it is our troops who are caught in the middle," said Senate Democratic leader Harry Reid of Nevada.
"We have seen milestones pass in Iraq before, with no lasting signs of progress," he said. "If today's sentencing is to be any different, we need to take a new direction in Iraq."
Bush, who supports the death penalty in the United States, pointed out that Saddam had an automatic right to appeal his sentence. "He will continue to receive the due process and legal rights that he denied to the Iraqi people."

'LANDMARK EVENT'
Snow told Reuters the verdict was proof of an independent judiciary in Iraq that operated fairly and openly.
"Today we witnessed a landmark event in the history of Iraq," Bush said at a campaign rally in Nebraska. "Saddam Hussein was convicted and sentenced to death by the Iraqi High Tribunal," he said to huge applause.
Bush, rying to fend off a strong challenge from Democrats in Tuesday's elections, has warned repeatedly on the campaign trail of the consequences of abandoning Iraq's fledgling government and has accused Democrats of attacking him over the war without offering their own plan.
Bush, on a 10-state swing where close races threaten traditional Republican strongholds, insists he was right to take action in Iraq to remove Saddam from power.
"Saddam Hussein was a threat," Bush said. "My decision to remove Saddam Hussein was the right decision and the world is better off for it," he said in a Nebraska congressional district Democrats have not won since 1958, but where this year's House race is close between Republican Adrian Smith and Democrat Scott Kleeb.
Bush earlier told reporters in Waco, Texas, before heading out to rallies in Nebraska and Kansas that Iraq had "a lot of work to do," but predicted history would record the Saddam conviction as "an important achievement on the path to a free and just and unified society."
Snow said it was "absolutely preposterous" to think the verdict was timed to help Republicans in the election, saying anyone who believed that must be "smoking rope."
Democrats took aim at Bush's policy. Former Democratic Sen. Max Cleland of Georgia said the death sentence would make no difference and predicted more violence.
"Well, you can hang Saddam Hussein from the rooftops, but it's not changing the situation on the ground, except to make two million Sunnis more mad against Americans and against Shias," Cleland told CNN's "Late Edition."

Copyright Reuters, 2006