If Nazi Germany had been conducting the occupation of Iraq, during the periods when military truck convoys were hit by IEDs and suicide bombers, this is what the Nazis would have done:

Every time one of their supply trucks were hit by an IED, they would have corralled and machine gunned everyone within 1 km or so. Then razed their houses to the ground.

This is the kind of thing they did in WW2 and it was VERY effective in shutting down insurgents.

America did no such thing.