Answer:
Iraq was fought through insurgency unlike many other wars like WW2, Korean War, and more. Insurgency is one of the hardest types of warfare today, one of the main reasons being the "sides" of the war are diverse and not 100% alike. A civilian in a warzone can pick up a rifle and automatically join that insurgency. Where in WW2, it was physical militaries with structure.
Step-by-step explanation: