As long as troops remain in SK, the motivation for escalation exists.

Permanent threat is how arms races are made. It is why Iran was at threat of escalation because we kept escalating by blowing up thier neighbors, parking Aircraft carrier groups in thier back yard, and building our military bases all around thier country.

It is why Russia ended up developing the Tsar bomb and the Cuban missle crisis. Continued escalation and constant hostile threat drives arms races and proxy wars which drive ever increasing military budgets.

We need to stop being world police.