Refuse to Occupy is a slogan that about 100 people in Israel have been spray painting in Hebrew. If you're caught painting this there, you will be detained as a terrorist.
This print is in solidarity with those people, tying in an American soldier referencing the occupation of Iraq.
Barron sketched the idea for this poster while in Israel during the summer of 2008, but didn't make the print until the recent attacks on Gaza in the begging of 2009.