Two weeks ago in this space, I wrote about the foolishness of a political leader like President Joe Biden who is so ideologically rigid, so thoroughly self-identified with his beliefs about the world that, when those beliefs turn out to be wrong, he can never afford to acknowledge the truth. This week, Biden provided yet another illustration of this foolishness by an address to the nation, occasioned by what anyone could see was America’s worst military disaster in nearly half a century. Yet not only did he fail to acknowledge the disaster, he treated it as if it were a triumph. “Last night in Kabul,” he began, “the United States ended 20 years of war in Afghanistan. The longest war in American history. We completed one of the biggest airlifts in history with more than 120,000 people evacuated to safety. That number is more than double what most experts thought …