[scarmig]

MacArthur also repeatedly tried to goad China into intensifying the conflict, against the direct orders of Truman.

There's the escalation with China/nuke part of things, and there's the total rejection of civilian control of the military part of things.

[nemo]

Yep, MacArthur was a great military strategist, but very politically naive. Truman really had no choice but to relieve him after MacArthur went off the rails and tried taking executive authority he didn't have to further military goals.