The base was used by American forces following the attacks of Sept 11, 2001.
Archived version: https://archive.is/newest/https://www.straitstimes.com/world/united-states/trump-says-bad-things-will-happen-if-afghanistan-does-not-return-bagram-air-base
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I posted this as a response to a different comment here but figured I’d copy/paste it in response to your question too;
Saudi Arabia has an alliance with Pakistan, including using nuclear weapons as a response in Saudi Arabia’s defense.
If Israel attacks Saudi Arabia, Pakistan responds. Bagram airport is only a couple hundred miles from the Pakistan border and an excellent place for the US to intercept any response from Pakistan headed towards Israel.
i wonder if china will get involved indirectly, since china and pakistan also are friends, and helped developed thier nukes.
I hope all this never gets far enough for us to find out.