A US naval blockade of Iranian ports in the Strait of Hormuz took effect on Monday and is now in its fourth day as of Thursday, with 13 ships turned around or stopped and no boardings reported. Officials including Pete Hegseth and Gen. Dan Caine briefed on the enforcement, which applies to all ships regardless of nationality heading to or from Iranian ports. Many details on naval deployments, Iranian losses, and specific statements remain unverified.