The U.S. will reestablish a permanent troop presence in Somalia to counter the al-Shabab terrorist group, reversing a decision by former President Donald Trump to withdraw the roughly 750 special operations troops who were previously stationed there. President Joe Biden approved a plan, presented to him by Defense Secretary Lloyd J. Austin III, that will draw on troops already stationed in neighboring countries to bolster U.S. counterterrorism efforts in Somalia, according to a senior administration official.