So let's talk about filibusters, obstruction, and the Senate in light of the 11th-hour deal on Tuesday that averted a midstream rules change by majority Democrats and a threatened Defcon I by minority Republicans over blockage of a slew of executive nominees.
First, a broader point. The United States Senate is unlike any other parliamentary body in the world. It has rules like the others, it has structure like the others, it has partisanship like the others. But it is less reliant on strict rules and less structured than any others. The Senate runs on unanimous consent for almost everything it does, and it's more of a delicate organism than a well-oiled machine. For the Senate to function, it needs comity, and to function well, it needs all of its members -- all of them -- to cooperate.
The rank-and-file members of most parliamentary bodies are cogs in the machine; some are bigger and more powerful than others, but individual cranks, lunatics, obdurate asses, showboaters, and recalcitrants become minor annoyances who can largely be ignored or steamrolled.
The individual members of the Senate are not so easily dealt with. Those who want to be (to use the more polite phrase) skunks at the garden party can divert and block the Senate in many ways, even if a majority of members and even leaders object. By denying unanimous consent, taking and holding the floor, turning some of the looser rules on their heads, and, especially, stepping in at critical times at the end of sessions to block action when time is precious, individual senators can wreak havoc -- and, sometimes, get their own way.