The answer is simple: They are hypocrites. They never stick to any deals or cease-fires they agree to and they blame Israel for all of their problems. For example, we have Arafat who claims that Israel is putting a stop to the peace process and that he is doing all he can to stop terrorism, yet at the same time is condoning terrorism and is asking for more suicide bombers. The only thing they listen to is force, and a force that can finish the job, not like the one the U.S. had in the Persian Gulf War (why is Saddam still in power?).
Colin Powell