Drills will include air combat exercises designed to improve ability to use smaller airfields in case its main bases come under attack.

The joint exercise at the Andersen Air Force Base, known as Cope North 2021, started on Wednesday and will run until February 19 and will see the base hosting F-35A joint strike fighters for the first time.
The exercise kicks off with an exercise designed to improve the three countries’ ability to carry out humanitarian operations in response to a natural disaster in the region, according to a statement from the US air force in the Pacific.
It also includes air combat drills designed to improve their flexibility and common communications ability.

one commander had said that one aim was to improve the forces’ ability to operate from small, rough airfields with limited facilities – also known as austere airfields– a move analysts said was designed to make it harder to “wipe out” US air power with missile attacks on major bases.