Here is an excerpt:
I argue that, doctrinally, all Indian tribes currently recognized as such by the U.S. government—all “federally recognized tribes”— necessarily were under federal jurisdiction in 1934. Under the doctrine of discovery (or discovery doctrine), the United States, like the European powers that preceded it, asserted jurisdiction regarding the Indigenous peoples within its claimed territories and assumed certain obligations to those peoples. As it developed this doctrine into the plenary Indian affairs power doctrine (or plenary power doctrine), the Supreme Court explained that the federal government had since its inception possessed this plenary jurisdiction regarding all Indians within the United States’ boundaries. It was part of the colonial relationship: because the United States claimed sovereignty over their territories, the Indians living there fell under the federal government’s jurisdiction.