Me thinks the same. Let Japan take care of their own History on their own. We do not need to baby sit Japan anymore and/or impose our own views upon them.
They are a very proud nation, rich History and perfectly capable to right the wrongs in their past.
We should leave Japan completely, for they are fully capable to protect themselves.
We should release them out of the contract drafted and signed in 1945 when the war ended, and let the Japanese decide their own fate on their own, the way they see fit.
Don't know about leaving them alone...mutual-defense pact would be fine with me. Let them take primary responsibility for their defense, keep our basing rights for the carrier group, move the Marines from Okinawa to Guam, agree we'll help each other in an emergency.