The unfortunate tactic of filibustering to block federal judicial nominees continues in the U.S. Senate.

The shoe was on the other foot recently in the U.S. Senate when the Republican minority succeeded in blocking one of President Obama's judicial nominees.

Majority Democrats expressed outrage when minority Republicans turned back an effort to end the filibuster of the nomination of Gordon Liu, a law professor at the University of California-Berkeley. But it was just a couple of years ago when Democrats, over the protests of Republicans, were doing the same thing to judicial nominations made by President Bush.

Senators engage in filibusters, a term referring to unlimited debate, to prevent an up-or-down vote, indefinitely postponing an issue and essentially defeating a bill or nomination.

Indeed, the GOP filibuster has succeeded in defeating the Liu nomination. Several days after the Senate vote, Liu withdrew his name for consideration to an appointment on the 9th Circuit Court of Appeals because he saw "no possibility of an up-or-down vote on the horizon."

Debate over the Liu nomination is the latest example of the bitter political fight that has developed over judicial nominees during the past 30 years, and tactics have escalated.

Routinely filibustering judicial nominees was unthinkable until the Bush II presidency, when Democrats, led by U.S. Sen. Charles Schumer of New York and Richard Durbin of Illinois, embraced the tactic. Even former U.S. Sen. and current President Barack Obama embraced the tactic, although he stated that filibusters were too frequently used to block judicial nominees.

Now that Obama is president, Republicans have adopted the escalation in tactics by using the filibuster to block an Obama nominee.

Such is the nature of politics. But it's unfortunate.

Judicial nominees of Democratic and Republican presidents are entitled to an up-or-down confirmation vote. But when one side adopts an unsavory tactic to achieve its political goals, the other is sure to do the same because unilateral disarmament guarantees defeat.