updated 3/11/13 Near the northern tip of South Dakota's Stronghold Table, where wind-whipped buffalo grass gives way to the Badlands' chasms and pinnacles, stands a hogan hammered from plywood and chipboard. Ten summers ago, Keith Janis, a rowdy, long-haired Oglala Lakota Sioux, roared out here in his truck, hooting and gesturing at the gray-shirted park rangers. This is Lakota land, he thought. The National Park Service has no business here. He pounded two cedar posts into the high prairie and defiantly strung a hammock beneath the stars. A Colorado couple helped him finish the hogan before winter. Janis, now in his 50s, sought to reclaim 133,000 acres of tribal land that the National Park Service had controlled since 1968. Earlier, the U.S. Air Force had used it for bombing exercises. But to the Lakota, the Stronghold, at the southern end of Badlands National Park and the northwest corner of