Scenario solved—marine joint exercises and restructured regiments exist in the status quo
Schifrin and Sagalyn 23- Schifrin is the foreign affairs and defense correspondent for PBS NewsHour, Sagalyn is the deputy senior producer for foreign affairs and defense at the PBS NewsHour
Nick Schifrin and Dan Sagalyn, "U.S. and Japan boost cooperation as Marines adapt controversial plan to counter China," PBS NewsHour, 1-13-2023, https://www.pbs.org/newshour/show/biden-japan-pm-agree-to-boost-military-spending-and-presence-in-asia-to-counter-china-- 嘉玮
And the U.S. is expanding its commitments. The U.S. now promises any attack in space would trigger a mutual defense provision. The U.S. and Japan will increase training on Japan's southwest islands, some of which are 1,200 miles from Tokyo, but just 100 miles from Taiwan's capital.
And the Marines will repurpose their presence in Japan into what they call a littoral regiment. It's designed to be more mobile, better conduct reconnaissance, and fight from remote islands. They will be equipped with not-yet-acquired anti-ship and anti-aircraft missiles. The Marines portray themselves as the best of the best, capable of responding quickly anywhere on the planet, including for the last 20 years fighting land-based counterinsurgencies.