> The simple reason is that global politics (at the UN) led to the partition of the Mandate

That was a piece of paper which changed nothing.

The Arab and Jewish populations had been in an escalating conflict for years, culminating in an all-out civil war. The Israeli population would have declared independence as soon as the British left regardless of what the UN said. Similarly the Arab states had no intention of letting Israel exist, and attacked as soon as the British left.

> That was a piece of paper which changed nothing.

It made the conflict the World's affair.