President Obama nominated an American Indian who had been the attorney general of Idaho to lead the Bureau of Indian Affairs. The nominee, Larry EchoHawk, is a law professor at Brigham Young University and a member of the Pawnee tribe. The agency manages 66 million acres of land and oversees Indian schools and other programs. Mr. Obama last month nominated Yvette Roubideaux as director of the Indian Health Service, a part of the Health and Human Services Department.