DUBAI/CAIRO — The Middle East war intensified on Tuesday with Iranian-backed Houthis in Yemen launching strikes on several Saudi cities, further embroiling a U.S. ally in the conflict, while U.S. forces hit multiple Iranian oil tankers and Iran targeted a U.S. base in Jordan. The Houthis attacked four cities in the south of Saudi Arabia, wounding 73 people and setting oil installations ablaze in what appeared to be a major expansion of the six-month-old war. As global oil markets were pricing in the Saudi attacks, the U.S. military's Central Command said it destroyed five Iranian crude oil carriers on Tuesday and posted video of the strikes, which it called a response to Iran's Islamic Revolutionary Guard Corps targeting a U.S. Navy warship with ballistic missiles twice over the previous two days. No Americans were harmed, the U.S. said. "Iran continues to try to hit U.S. naval ships, and for every time they do that or try to do that, they're going to lose tankers," U.S. Secretary of State Marco Rubio told reporters during a visit to Colombia. Iran then retaliated with a ballistic miss