Uh, I beg to differ. It is theirs - they are building on the lands - they are "contested" lands - not now and never have been Palestinian lands. 

Most of the so called Palestinians are originally Egyptian or Jordanian, where in both countries they were afforded the same status as the current refugees are in the European countries, except that the "Palestinians" we're never considered for citizenship - they were at best tolerated. 

There were no claims by any Arab / Muslim group for lands now considered "contested" prior to 1967. 

Anyway, it doesn't matter, because Trump will use the monetary influence the US has over the UN to change the narrative. Give it a few years, and perhaps the Palestinians will decide that they'd rather have a part of something than all of nothing. Peace will be determined by money - the US will stop funnelling dollars into Gaza unless the leadership gets on board with a 2 state solution, which they have repeatedly rejected up to now.