It's been a VERY long time,since I've thought of him,but that's my still vivid memory...he was a faaaaaaaaaaaaaaaaaaar lefty.I don't know anything at all about his "defending" America,which might have come at a later time.But IF you have the stomach to read his "USA",you'll see that his writings weren't pro-American.
Even as a kid,I was rapidly anti-Commie and having to read dos Passos' works,make me want to shred the books.
I read 'Mid-Century' before I read his USA trilogy, and was astounded to find him such a commie! lol!
Orwell was a more subtle man than you credit him, imo.
He saw through the commie hoax before his comrades - give him that.