The USA is not at war. The air strikes are a matter of protecting ethnic minorities.

The reason President Obama decided the spill over from the Syrian civil war into Iraq was an emergency enough to respond to is because of the large number of diverse cultures within the borders of Iraq. There was no Iraq military to support the border, hence the spillover from the civil war. And the last component was the methodology used by the Islamic State (which could be names The Islamic group of nut cases in cooperation with Western fanatics) which killed men and stole women and it was anyone's guess what was happening with children.

The country of Iraq. It was a sovereign country able to hold it's borders and conduct sovereign issues of any state. The name has come from the ethnic group of Iraqi or Mesopotamian Arabs. They account from about 75% of the population of Iraq. They speak Mesopotamian Arabic.