Thanksgiving. We're all familiar with the tale, a minor event in 1621 elevated to the level of propaganda and myth; the Pilgrims were to celebrate their traditional feast of the fall harvest when a group of Native People arrived to share their bounty with the hungry new arrivals.
This communal luncheon among two disparate ethnic groups became a national holiday in 1863, and thanks to the imaginations of a few illustrators at the turn of the century, we inherited a picture of peaceful coexistence among half-naked savages and Puritans dressed in goofy black hats.
The Pilgrims are often referred to as "The First Settlers," which implies that Native Americans merely wandered aimlessly around the continent awaiting the arrival of a landlord. In fact, by the time the Mayflower arrived, these 'native' settlers had been 'settled' on the North American continent for thousands of years, but we rarely let facts get in the way of romantic titles.
Tradition holds that the Pilgrims were thankful for their families, their God, a successful harvest, and their continued survival. Their guests had plenty to be thankful for too, but this is rarely mentioned during Thanksgiving celebrations.
1) Booze - Firewater was a great evolutionary step for Native Americans; it allowed them to experience religious ecstasy without having to resort to the inconvenience of fasting, vision quests, and magic. A wise, high-maintenance shaman is replaced by a non-union liquor store clerk. Progress = convenience.
(Another big advantage for booze: when compared to peyote, it tastes better and is less filling.)
2) Small Pox - Without this gift from generous White Man, the native population would have gone unchecked, encouraging overcrowding and the subsequent destruction of natural resources intended for use by others more experienced at urban development.
3) Professional Sports - Without this White European cultural phenomena, they would never have been immortalized by such teams as the Cleveland Indians, the Washington Redskins, and the Atlanta Braves. A side-effect is that thousands of white racists in Georgia now own foam-rubber tomahawks and know the melody of an ancient Native American pop song. (Hey-ah-hey-ah-hey)