"As we clear away the debris of a hurricane, let us also clear away the legacy of inequality," Bush said during a national prayer service with other political leaders and religious figures from the affected region at the National Cathedral.
Also yesterday, White House officials said that taxpayers will pay the bill for the massive reconstruction program for the hurricane-ravaged Gulf Coast and that the huge expense will worsen the nation's budget deficit.
Several dozen evacuees and first responders, all from New Orleans, filled one side wing. The president and his wife Laura sat solemnly in a front pew along with Vice President Dick Cheney and his wife Lynne.
Before Bush's remarks, Bishop TD Jakes, head of the 30,000-member Potter's House church in Dallas, delivered a powerful sermon in which he called upon Americans to "dare to discuss the unmentionable issues that confront us" and to not rest until the poor are raised to an acceptable living standard.
"Katrina, perhaps she has done something to this nation that needed to be done," Jakes said. "We can no longer be a nation that overlooks the poor and the suffering, that continues past the ghetto on our way to the Mardi Gras."
Bush, faced with continuing questions about whether help would have been sent more quickly to the storm zone if most victims had not been poor and black, echoed those themes in brief remarks that were rich with religious references.
"Some of the greatest hardships fell upon citizens already facing lives of struggle, the elderly, the vulnerable and the poor," he said.
"As we rebuild homes and businesses, we will renew our promise as a land of equality and decency and one day Americans will look back at the response to Hurricane Katrina and say that our country grew not only in prosperity but in character and justice."
As on Thursday, when Bush called for "bold action" to overcome poverty and discrimination, he offered no specific actions that should be taken.
At the White House, director of Bush's National Economic Council Al Hubbard said the disaster costs - estimated at $200 billion and beyond - are "coming from the American taxpayer".