WASHINGTON. Four years ago, when then-Sen. Barack Obama was campaigning for president, he said of Afghanistan: This is "a war that we have to win." He also claimed, "The Afghan people must know that our commitment to their future is enduring because the security of Afghanistan and the United States is shared." But after three years of Obama's being commander in chief, it ought to be clear that he never really believed his own campaign rhetoric. Now, in the aftermath of recent setbacks, his words are further evidence of presidential ambivalence and uncertainty.