Jews were already migrating to British Mandate since the 1900s (read about the Aliyah). Even without Hitler, communist expansion would have resulted in a World War 2 (with different players) and a mass Jewish exodus (from Russia, which happened later on in our timeline). Jews were already carrying out terror attacks on both Palestinians and British troops and Britain was already stretched thin after WW1.

The creation of a rogue Israel happened with decolonization, and while it might have been delayed, was inevitable.