The whole conflict is complicated but can be blamed on the acts of Western (more correctly, British) Imperialism and how poorly the situation had been handled back in the day. ...Wait, that's not correct, the conflict has been there since the Jews were exiled from Jerusalem during the Roman times, and hell, probably even before. It's something that will probably never be solved, mostly due to religious reasons, but also because the area hasn't seen a non-violent act in just about 2000 years. The Crusaders slaughtered all the Muslims during the 1000s, the Ottoman era came to an end because of the Brits and what can be seen in the Middle East are beastly, vile and greedy acts when bunch of people attack bunch of other people with vague reasons, but most likely don't know the reason of the conflict at all.
Most Israelis and Palestines are probably good people and what appears on the news is just the work of some lunatics like Hamas or Army of Islam etc. or some Israeli soldier who decided it would just be dandy to cap a few Palestines just for kicks. Same thing what the Americans have done in Vietnam and Iraq (My Lai massacre, Abu-Ghraib, Gitmo, etc.). Ruanda? Nazis? Soviets? Iraqis? Stating the obvious, Israel is just one of those places on Earth where humanity is driven by beastly AKA violent acts. Hell, lately it has been demonstrated that the Palestines don't even get along themselves, so wiping Israel out of the map like a certain other lunatic stated about two years ago wouldn't solve anything.
So to actually be on-topic, I think Jarre should hold his concert there, fight back against the risks and promote the values of tolerance and human rights. If it succeeds, well, it would be extremely grand and hopefully have some impact on the area (doubtful). If something goes wrong, well, the organizers no doubt take this into account and it just remains to be seen if the security's strong enough and if some lunatics pay no attention to the concert's actual meaning and do something despicable.