They can't claim independence while there are 400,000 settlers on their lands, that would mean they would get into a war with Israel as the Palestinians would want that land the settlements are on, back. If they leave the settlers, they've lost their land. You can claim independence all you want, but there are thousands of Israeli 'security forces' standing about in the West Bank. They would probably have to accept the boundaries the barrier is being built on. They would not get East Jerusalem as their capital, where 200,000 Palis live.