Latin America: Bitterly refusing to concede the presidential election he lost, Andres Manuel Lopez Obrador vows to destabilize Mexico as payback for his defeat. The government will have to deal with him firmly. And that's a shame, because the final call, set for Sept. 6, on Mexico's July 2 presidential election should be pure celebration. The country should rightly recognize its free and fair vote, its emerging new parties and its solid institutions — all of which have come about in a mere decade of democracy from a one-party state — and winner Felipe Calderon should be able to begin...