Israeli military forces have made accidents, as have American forces. Just because the Israelis are not intending on killing civilians, they still could kill some accidentally. Already there are reports of Lebanese civilians having been killed, though, yes, those civilians could actually have been combatants.
Certainly..But the chances are less of his being harmed by staying in a major hotel in Beirut than by walking near his office in DC which has just called a crime emergency here.