They don't care, Americans destroyed every building in Korea (the famous "no targets remaining" quote). Giving almost every right-wing group in the country rifles and stinger missiles, to throw the country into a permanent state of civil war, has the exact same effect as carpet bombing.

Minus the invasion consolidating into a left-wing anti-American socialist front, which happened in Korea, Vietnam, Laos and Cuba.

A permanent civil war, lead by a right wing government, still allows the export of surplus value which is collected by Americans. A left-wing government would try to keep that surplus inside the country to further develop means of production.

It's called Shock therapy and even some liberals (the most politically educated and articulate) are conscious of this happening.

Henry Kissinger's life work is architecting American interventions that result in right-wing reactions rather than left-wing ones. Give all the right-wing groups guns, they kill the left, the country remains defenceless from extraction, and by the time Americans intervene it's multiple squabbling right-wing militias instead of a united socialist front with an industrial base and functioning anti-air missiles.