The theme of Obama’s sermon today is not new. Early last spring, shortly after he had declared, as you recall the question arose as to whether or not he was “really black,” — meaning, “was he a legitimate potential black leader?”
The old guard of the black civil rights movement — Sharpton, Jesse, and all the other angry, embittered, largely rejected leaders were still sneering at the upstart pretentions of this half-white, not-decended-from-slaves, exceptionally well-educated guy who was not under their thumb. But a particular black minister in Arkansas (I think), gave a very compelling sermon to the effect that maybe Obama represented the “Joshua generation.” His point was that, for all his many efforts, and the fact that he truly walked with God, Moses and the generation of Jews who left Egypt after having been slaves were made to wander in the desert, and were never allowed to enter the land of Israel to be free men in their own land. (Remember — throughout slavery, and, 100 years later during the heydey of the Civil Rights movement, black Americans regarded themselves as a latter day version of the Israelites in Egypt.) For that honor, God picked the leader of a new generation, untainted by slavery: Joshua.
The Joshua analogy was, and remains a brilliant metaphor. And surely it contains real truth about the nature of appropriate leadership, and what experience fits a leader for a new age– whether or not Obama gets the nomination or wins the election. So you can see why he would choose to cite that text any time he can.