This weekend in Selma, Ala., marchers will commemorate the 40th anniversary of the march across the Edmund Pettus Bridge in that city. The violence unleashed by Southern sheriffs and racial vigilantes on that day galvanized President Johnson to push through the Voting Rights Act, giving blacks the right to vote in the South for the first time since the brief reconstruction period after the Civil War.

Now 40 years later, that right to vote is once more at risk. When President Bush met with the 43 members of the Congressional Black Caucus, Rep. Jesse Jackson Jr. -- I report with some pride -- asked him if he would support extension and strengthening of the Voting Rights Act when it comes up for renewal in 2007.

Bush responded that he did not support voting rights for the District of Columbia. Jackson said that was not what he asked; he asked about extending the Voting Rights Act. Bush replied that he was not aware of the act and would look at it when it got to his desk. The president's passivity would enable House Majority leader Rep. Tom ''the Hammer'' DeLay to torpedo the act, just as he has real voting-rights reform.

The president has been eloquent in promoting democracy across the world. He said he would tell Russian President Vladimir Putin that democracies should be founded on ''the rule of law, and respect for human and rights and dignity.'' Bush has argued that democracy is so important in Iraq that it alone is worth Americans' dying and killing for. The interim Iraqi constitution protects the rights of women and minorities to vote.

But in America, Bush and his party are undermining the right to vote -- and the right to have one's vote counted. The glaring contrast between Bush's rhetoric abroad and his record at home raises deep questions about his true intentions.

When Johnson signed the Voting Rights Act, he predicted that there would be a fundamental upheaval in the South, and that Democrats might well lose that region for a generation. He got that right. Republicans became the party of white sanctuary, using racial fears and cultural insecurities to attract votes. And a solid South built on Jesse Helms' tactics remains the foundation of GOP majorities in Congress today.

Now in this divided nation, the undermining of voting rights -- and the unwillingness of the majority party to defend them -- is spreading. We saw it in Florida in 2000, where a partisan secretary of state, head of the Bush campaign in Florida, purged qualified black voters from the voting lists. We saw it once more in 2004, in Ohio. Once more the secretary of state in charge of the election was a rabid partisan and co-chair of the Bush campaign. Once more, African-American voters were disqualified improperly. Machines without paper records, made by companies headed by pro-Bush partisans, were adopted for use. When black registration went up, the number of machines in black districts went down, creating lines that lasted for hours.

In the midst of these outrages, the White House is absent without leave. Legislation has been introduced at the national level to require machines that provide a paper record, and to ensure that election officials are nonpartisan, rather than partisan operatives like J. Kenneth Blackwell of Ohio. Bush is silent on the legislation. The Republican leadership in the Congress has already indicated that legislation will not go forward.

A constitutional amendment to guarantee the right to vote, to ensure that residents of the District of Columbia have the same right to vote as residents of Baghdad, and to set up federal rules for fair elections has been proposed. The president is silent. The Republican leadership in the Congress has already indicated its opposition.

And now the Voting Rights Act -- which Bush knows well as a former governor of Texas -- must be renewed and strengthened. The president claims ignorance. The Republican leadership in the Congress, dependent on its strength in the South, will determine its fate.

Martin Luther King knew that progress towards equal rights depended on gaining the right to vote. But today, Republicans are shameless in their disregard for that right and Democrats are too passive in defense of it. It will require a renewed movement of concerned citizens to revive the right to vote.

In Selma, Ala., 40 years later, we will mark the anniversary of the march that forced Congress to act. Now once more fierce resistance to voting rights is growing and it will take fierce popular pressure to defend the right to vote in this country, even as our troops die to provide that right in Iraq.