The clandestine American military campaign to combat Al Qaeda’s franchise in Yemen is expanding to fight the Islamist militancy in Somalia, as new evidence indicates that insurgents in the two countries are forging closer ties and possibly plotting attacks against the United States, American officials say…

The military drone strike in Somalia last month was the first American attack there since 2009, when helicopter-borne commandos killed Saleh Ali Saleh Nabhan, a senior leader of the group that carried out the 1998 attacks on the American Embassies in Kenya and Tanzania. Although it appears that no senior Somali militants were killed in last month’s drone strike, a Pentagon official said Friday that one of the militants who was wounded had been in contact with Anwar al-Awlaki, the American-born radical cleric now hiding in Yemen. The news that the strike was carried out by an American drone was first reported in The Washington Post this week…

Even as threat warnings grow, American officials say that the Shabab militants are under increasing pressure on various fronts, and that now is the time to attack the group aggressively. But it is unclear whether American intelligence about Somalia — often sketchy and inconclusive — has improved in recent months.