Republican Senator Rand Paul of Kentucky delayed Senate business yesterday by launching a filibuster that lasted nearly 13 hours. The ninth-longest filibuster in Senate history and the longest since 1992 focused on the president’s power to order an American citizen killed on U.S. soil. Paul managed to delay a planned confirmation vote on President Barack Obama’s nominee for CIA director, John Brennan. Senators are likely to confirm Brennan today, but Paul’s tactic served two longtime historical purposes of the filibuster: slow down Senate business and call attention to an issue of national importance. To my knowledge, the last lengthy filibuster of this kind happened when Bernie Sanders talked for more than eight hours against the December 2010 deal to extend most Bush tax cuts.

Eight other senators joined Paul’s filibuster yesterday: seven Republicans and Democrat Ron Wyden of Oregon. Iowa’s GOP Senator Chuck Grassley did not take part.

In related news, some Senate Democrats are warning that the majority may revisit filibuster reform because Republicans continue to demand a 60-vote majority for almost any kind of Senate business. That was entirely foreseeable. But Democrats missed their best chance to change the rules at the beginning of this year’s Congress. They should have listened to Senator Tom Harkin, who has been trying for years to curtail the abuse of the filibuster.