The ghosts of Baghdad and Kabul should be enough to silence any serious talk of sending American troops into Iran. Yet here we are again, with voices in Washington and Tel Aviv whispering that only boots on the ground can neutralize Tehran’s nuclear ambitions, its local allies and its regional mischief. They are wrong. An American invasion of Iran would be a strategic catastrophe, a moral failure and a self-inflicted wound from which the United States might never fully recover. First, the military and logistical reality is brutal.…