The United States is engaged in a police action with north Korea that is in a state of cease fire. It never officially ended. It is ongoing.
Foot print in Asia is not the reason. We are there as part of the UN mission in the ongoing police action mission. Negotiations are still in progress at Panmumjon
We have major troop and air deployments in Asia..... in Afghanistan
It's just silly to think of Afghanistan, which we can barely keep supplied, in the same vein.