On one of the most shameful days in the modern history of the Senate, the Republican minority on Thursday prevented a vote to allow gay and lesbian soldiers to serve openly in the military of the United States. They chose to filibuster a vital defense bill because it also banned discrimination in the military ranks. And in an unrelated but no less callous move, they blocked consideration of help for tens of thousands of emergency workers and volunteers who became ill from the ground zero cleanup after the attacks of Sept. 11, 2001.

The senators who stood in the way of these measures must answer to the thousands of gay and lesbian soldiers who must live a lie in order to serve, or drop out. They must answer to the civilians who will not serve their country when some Americans are banned from doing so for an absurd reason, and to the military leaders who all but pleaded with them to end this unjust policy. They must answer to the workers who thought they were aiding their country by cleaning up ground zero.

The Senate majority leader, Harry Reid, said that he would allow another vote on repealing the military’s “don’t ask, don’t tell” policy in a free-standing bill later this month. That long shot is likely to be the final test of whether the Republicans are interested in allowing military equality.

Republicans wanted extra days of debate, demanding the right to amend the defense bill that contained the repeal provision, and essentially killing the bill without quite admitting to it by suffocating it of time. Mr. Reid said he had concluded that they had no intention of repealing the repressive measure, so he called for a vote.