Here. An excerpt:

Every schoolchild is taught that the holiday of Thanksgiving commemorates the feast the Pilgrims arranged to thank the Indians for their friendship, for sharing their land, and for showing them how to grow, harvest, and store food. Accounts say that the generosity of the Indians saved the colonists from starvation during the harsh New England winter of 1620.

Very few schoolchildren are also taught, however, about the deprivations and atrocities that occurred to the Indians afterwards, first at the hands of the colonists and then by the United States government. Ironically, if the United States believes today that it has a poor immigration policy, imagine how self-destructive the Indians’ immigration policy was by welcoming the very people who would soon seek to destroy them.

– See more at: http://blog.oup.com/2013/11/thanksgiving-american-indian-treaty-violations/#sthash.j8seTGCk.dpuf