The U.S. military on January 19 carried out another round of strikes against Yemen's Iranian-backed Huthi rebels, targeting missile launchers that were preparing for attacks on shipping in the Red Sea, the White House said. "This morning, U.S. forces conducted three successful self-defense strikes against Huthi targets in Yemen," National Security Council spokesman John Kirby said. It was the fourth "preemptive action" taken in the past week against Huthi missile launchers, Kirby said, adding that the actions were "done in self-defense, but it also helps make safer international waters for both naval vessels as well as merchant shipping."