There is NO SOLUTION possible when 2 countries claim ownership of some land area. That Ladakh region in dispute is a desolate frozen piece of shxt. But ego will not allow either country to accept defeat.
If Mexico claims ownership of part of CA, will Americans negotiate partitioning CA? Nope, Nada, Never, Nein, Negative.
How about Mexico return Baja to Las Californias - I bet if there was a vote the residents of Baja would prefer to be American.