For the last four years, Senate Republicans have used the power of the filibuster to block legislation, bottle up nominees to courts and government departments, and strangle federal agencies, even though they are in the minority. On Thursday, they hit a new low. They successfully filibustered Chuck Hagel, President Obama’s nominee for defense secretary, the first time a cabinet nominee for this post has been prevented from receiving an up-or-down vote.

The Republicans claimed they needed more information about Mr. Hagel, though he answered every question at his confirmation hearing and provided more paperwork than usual. As a former Republican senator, in fact, Mr. Hagel is better known to his old colleagues than most nominees. A delay of another week or two, which some members said they were seeking, is not going to change anyone’s opinion.

Some senators tried to use the nomination to reignite last year’s smoldering fight over the deaths of American diplomats in Benghazi, Libya, demanding to know when Mr. Obama spoke to the president of Libya after the attack. This exercise in political score-settling obviously has nothing to do with Mr. Hagel, and the White House had no obligation to respond, but it did anyway, saying Mr. Obama spoke to the president the day after the attack.

Did that satisfy the Republicans? Of course not. They just moved on to some new excuse to block Mr. Hagel, since the entire procedure was really about denying Mr. Obama his nominee for as long as possible. Harry Reid, the majority leader, explained what was actually happening. “I guess to be able to run for the Senate as a Republican in most places of the country, you need to have a résumé that says I helped filibuster one of the president’s nominees,” he said. “Maybe that helps. Maybe that keeps a Tea Party guy from running against you.”