If you were judging by the death of Nawres Hamid, an Iraqi-American contractor killed in late December after an American base in Iraq was mortared by a Shiite militia believed to have ties to Iran, the answer would be obvious: enough to risk war. After all, the president cited Hamid's death in going after that militia and then drone-assassinating Iranian Major General Qassem Suleimani. In response to the mortar attack, U.S. air strikes in Iraq and Syria killed at least 25 Iraqi militia fighters and then, as January began, that drone strike near Baghdad International Airport took out a figure who was often considered the number-two man in Iran, as well as its possible future leader. In addition, it killed an Iraqi militia commander and eight other people.