What’s more, Al Shabab now has a web of followers and informants imbedded in Afghanistan, East Africa and even in the U.S. where it has sought financial support from the Somali diaspora.

Some of these followers have carried out suicide bombings, and some are now suspects in the recent terror attack in Kenya, where more than 60 civilians were killed and many more were wounded. The fact that Al Shabab claimed responsibility for that attack shows how serious a threat the group poses not only to Kenya, but also to the rest of the world.

With Al Shabab now dispersed and blended into the mainstream with smaller cells, distant from the central command but capable of carrying out autonomous acts of terrorism, there is no question that Al Shabab is very much a threat to the U.S., including on American soil.