W: The Original Countermajoritarian
This brings us to the filibuster. The primary objection to the filibuster is that it is countermajoritarian. That is, it enables a minority of senators (41 in the current Senate) to block proposed legislation and nominations. But there is nothing odd about that. In a government determined to avoid "capture" by any faction and designed to protect minority as well as majority interests, our entire government's structure of checks and balances is deliberately premised on countermajoritarian procedures.
Consider the Electoral College. George W. Bush won the 2000 election even though he received 500,000 fewer popular votes than his opponent. What could be more countermajoritarian than that? Indeed, the Senate itself was quite consciously designed to be countermajoritarian, with two senators from each state, regardless of population. As a consequence, although the Republicans currently have 55 senators, they represent well under half the people in the United States. Countermajoritarian processes are fundamental to the American system because they protect substantial minority interests against the bullying of marginal and transitory majorities.
The Senate filibuster is a classic example of such a procedure. The filibuster has been recognized by the Senate at least since 1790. Although it has been used most often to force compromise on proposed legislation, it has also been used to encourage compromise on executive and judicial nominations. The filibuster was first used to block a judicial nominee in 1881, when it was invoked against Rutherford B. Hayes' nomination of Stanley Matthews to the U.S. Supreme Court. (Matthews was eventually confirmed.) From 1950 to 2000, the filibuster was used at least 17 times in the context of judicial nominations, most famously in the successful effort of Republicans to derail President Lyndon B. Johnson's nomination of Abe Fortas as chief justice in 1968.
[Geoffrey R. Stone, "The Nuclear Option", The Huffington Post, 15 May 2005.]