She seems like an American Palestinian who's there to protest the war. She's obviously on the Israeli side of the warzone, otherwise they simply would have shot or arrested her.
It's apparent that she is one exceptionally brave soul, and perhaps the only reason she's still alive is due to the camera running with a person who may have been sending live video to the US while the event was taking place.
That hasn't always stopped the IDF though, in regards to Rachel Corrie.