From Holden:

The army now says the explosion in a U.S. military dining hall in Mosul yesterday was the result of a suicide bombing. This is bad news, worse than if the tent had been hit by a rocket. It means that the insurgency has infiltrated the base (where there is one suicide bomber there must be others), and it also means that the new concrete and steel mess hall Halliburton is building for the base can’t protect the soldiers from a similar attack.