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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Yep, and I don’t know how he’s planning on getting the Taliban to give that base back.