This happens in my TL Stars & Sickles.
I think the consequence for the domestic US sphere depends largely on the President in office at the time, since that affects perception of them. Overall though, there would probably be a militaristic response to other foreign policy crises. "Rollback" might become more popular than containment. I come to this conclusion because of a difference in the generational cultures of American voters in the early 1950s compared to the mid-to-late 1960s, which was the heyday of the US protest movement against Vietnam. Communism wasn't just seen as an existential threat but an imminent one. IMHO the veterans of WWII are probably more likely to get their backs up about "commies trying to start another damn war". After all, from their perspective they went through WWII to protect freedom, they aren't going to lie down and let the Soviets take it away from them. That's the popular narrative anyway.
In my TL, which reflects my opinion of how it would go, the US isn't going to be able to maintain the forces necessary to defeat the communists in China. They're going to have to withdraw eventually and when they do, the KMT will collapse. I'm not one to believe in a CCP-ruled North China and a KMT South China, even if the KMT was strongest in Guangdong. Besides, it's an overdone trope. Also, again in my TL, but which I think is relatively likely, is that the Americans are too overstretched to intervene in Korea so the DPRK conquers the whole peninsula. Which in the long-run actually makes Kim Il-Sung less powerful, meaning he is likely to get ousted and never founds the political dynasty that runs the OTL weirdo-world that is North Korea.