For France, we see "Phap là một nước tư bản." So shouldn't this entry accept the answer even without "chu nghia?"
Nope because if you leave out "chủ nghĩa" you're left with "xã hội" which means "society" and never "socialist" or "socialism".
Why is it reversed?
Chủ nghĩa xã hội is what is said previously.
No, I don't think so. I think Vietnam is being ruled by only party.