The filibuster may be unconstitutional, creating as it does a mechanism for a Senatorial veto.
One thing's for sure: Filibusters are also pre-constitutional. They are even pre-colonial.
The original filibusters were pirates of the Caribbean, and the contemporary Senate procedure continues to bear traces of the word's origins in the disruptive and lawless practices of the privateers who boosted the goods of ships traveling under Spanish sail. Later, the word came to describe an American movement with a base in the pre-Civil War South to seize Spanish West Indian and Central American lands and goods in the name of Manifest Destiny.
The word derives from a Dutch term for pirate and began to be applied to efforts "to hold the Senate floor in order to prevent a vote on a bill" in the in the 1850s, according to the Senate Historical Office. It is believed to derive from the Dutch word vrijbuiter, which means "to plunder," with vrij meaning "free" and buit meaning "booty."
And booty, according to Michael Sheen, a retired Chicago English teacher who writes the WordMall blog, means "collective plunder or spoils" such as "household goods seized and carried off" by armies.
These "freebooters" or "filibusters" traveled under no nation's sail -- they used various iterations of the Jolly Roger, instead -- and often sought to "privateer" goods and gold being transported by Spanish ships in the Caribbean, from slaves to gold. The word to describe them was first recorded in English in the late 16th century, according to the Oxford English Dictionary.
Filibustering first took on a political meaning in the early 19th century when it was transferred from pirates who seized goods to individuals who sought to seize goods, land -- and states.
According to PBS's The History Detectives:
In the 1800s, the term took on new meaning, referring to a group of adventurers who, without the consent of the American government, tried to assume power in a number of Latin American and Caribbean countries. Filibusters were intent on overpowering the 'lesser peoples' despite neutrality laws that forbid Americans from privately engaging in warfare with other countries.
Cuba, Honduras, Nicaragua, Costa Rica and Mexico were all victims of filibusters from 1830 to 1860.
Famous filibusters were larger than life characters such as Narciso Lopez, a Venezuelan-born soldier who, aided by sympathetic Southern money, liberated Venezuela from Spanish rule. He then attempted three times to free Cuba.
William Walker, a southerner from Tennessee, annexed parts of Mexico and named himself president. In his proclamation of control over Lower California (then part of Mexico), Walker explains why the territory was rightfully his, an explanation that neatly sums up the filibuster movement.
Thus abandoning the peninsula, and leaving it as it was "a waif on the waters," Mexico cannot complain if others take it and make it valuable. On such considerations have I and my companions-in-arms acted in the course we have pursued. And, for the success of our enterprise, we put our trust in Him who controls the destinies of nations, and guides them in the ways of improvement and progress.
Despite the vehement objections of the Mexican government and the anger of the U.S. authorities, many Americans thought this was a triumph for filibustering. However, Walker eventually gave up, finding it too difficult. He was tried by the U.S. and acquitted.
Perhaps it is appropriate given the history of the filibuster movement that the longest filibuster in U.S. history came from a Southern senator, the late Strom Thurmond of South Carolina, who held out for 24 hours and 18 minutes in opposition to the Civil Rights Act of 1957. After all, according to PBS, "The filibuster cause was successful largely thanks to a strong support base in the South" where "parades were held in their honor, songs written and their adventures glorified."