This is the same type of thing that happened in Vietnam, the enemy used the borders of other countries to hide from the war. We lost that war because we used a political scope, to fight it. If we do not cut off weapon, supply and manpower lines in this war, we will lose. It is that simple. If we know that Iraq is supplying weapons, and we do not bomb their factories, we admit that we are weak. We know what weakness in the face of Islam gets you.
Then why are we winning so spectacularly now, despite those problems?