BEIRUT (AP) — A U.S. airstrike targeting facilities used by Iran-backed militias in Syria appears to be a message to Tehran delivered by a new American administration still figuring out its approach to the Middle East. The strike was seemingly a response to stepped-up rocket attacks by such militias that have targeted U.S. interests in Iraq, where the armed groups are based. The group targeted is one of the most powerful Iran-backed militias in the Middle East known as Kataeb Hezbollah, or the Hezbollah Brigades. The attack is likely aimed at sending a message to Tehran that the U.S. will not tolerate attacks against American interests in the region. It comes as the Biden administration faces an uncertain road in its attempts to resurrect the 2015 Iran nuclear deal.