I'm not sure the customs official knows where you came from (unless they explicitly ask, of course), because in my experience normally you get off the airplane and join a common queue. I think your passport counts a lot more when it comes to how strict the scrutiny is going to be. I'm assuming you're American, if you had an Iraqi passport, maybe you would have to answer a few more questions.

Not the EU, but I once accidentally entered Switzerland in the Zürich airport. The passport counter was unmanned and the doorway next to it was open, so I assumed there is another checkpoint somewhere further.

When a guy started chasing after me 30 seconds later I realized my assumption was wrong. But there really wasn't a way to know.