The Senate filibuster has been used sparingly throughout most of
U.S. history. But several times when the minority has abused the
tool, the majority has responded by changing the rules. History
may soon repeat itself. The filibuster, as originally designed,
did not allow the majority party to call for a motion to end
debate — senators could obstruct endlessly. That changed early
in the 20th century, after the minority escalated its use of the
filibuster toward the end of congressional sessions, running out
the clock when the majority did not have the luxury of waiting.
In 1917, a Senate majority changed the rules to make it possible
for the majority to end debate. The new rule set “cloture” at 67
senators. In the 1960s, around the time of civil rights
legislation, the minority began to use the filibuster with
increased frequency. In 1975, a frustrated Senate majority again
responded by changing the rules, lowering the cloture threshold
to 60 votes — where it has remained ever since. Nearly four
decades later,