It was a protest against the British government bailout of the East India Company - the largest commercial entity in the world at the time. Today, we would call it 'corporate welfare. The nature of that bailout undermined the profits of American merchants who couldn't compete against the 'welfare' tea subsidized by the British government. Patriots today continue to have a low opinion of government welfare.
Two hundred & forty-six years ago, yesterday, angry colonists dressed unconvincingly as 'natives' to board the ships, and dump 340 chests of cheap Chinese tea into Boston harbor. It all belonged to the East India Company. Soon after Boston, there were 10 other 'tea parties' up and down the colonial Eastern seaboard in protest of 'corporate welfare.'
Courtesy of History dot Com:
"The (1773) Tea Act allowed the East India Company to unload 544,000 pounds of old tea, commission-free, on the American Colonies at a bargain price.
Cheaper tea sounds good, says Carp, but for the Sons of Liberty—many of whom were merchants and even tea smugglers—the Tea Act smelled like a ploy to get the masses comfortable with paying a tax to the Crown.
“You’re going to seduce Americans into being ‘obedient colonists’ by making the price lower,” says Carp. “If we accept the principal of allowing parliament to tax us, they’ll eventually make the taxes heavier on us. It’s the slippery slope argument.”
"...There’s this idea that the Boston Tea Party was the rallying cry that galvanized the colonies for revolution, but Carp says that many strong opponents of British rule, George Washington among them, denounced acts of lawless and violence, especially against private property.
While the Tea Party itself didn’t mobilize Americans en masse, it was Parliament’s reaction to it that did. In 1774, the UK passed what are known as the Intolerable Acts or the Coercive Acts, a series of punitive measures meant to teach the rebellious colonists who was boss.
Many of these sanctions were levied on the Massachusetts Colony and Boston itself, including the closing of Boston Harbor, replacing Boston’s elected leaders with those appointed by the Crown, and forcing the quartering of British troops in private homes.
“Taxation without representation was a dangerous precedent in and of itself, but now they were messing with the Massachusetts charter,” says Carp, “taking away rights that Massachusetts had previously enjoyed. As uncomfortable as some colonists might have been with the Tea Party action itself, they were way more uncomfortable with the authoritarian reaction by Parliament.”
In response to the Coercive Acts, the First Continental Congress met in 1774 and Jefferson wrote “A Summary View of the Rights of British America.” Revolution was officially in the air."