Ballistic missiles are deadly and difficult to intercept (unless you have a national missile defense). They are very conspicuous, with early warning radars picking up their signature long before they reach their target. Forewarned U.S. personnel were able to find shelter at Al Assad airbase long before Iran’s not-so-discreet rockets hit. When they finally arrived Automated Centurion Gatling cannons unleashed a hail of bullets shooting down several. Maybe that option isn’t such a good idea after all.