Of course the far left (communist) hate Watters because hes always making them look silly.
You wouldn't recognize a communist kid if one came and bit you in the ass.
A. He was being sarcastic
B. Usually, You wouldn't recognize is followed up with something related to it. I. E. You wouldn't recognize a book if you read it. In this case, "You wouldn't recognize... If he was reading the Communist Manifesto and quoting Karl Marx."
You aren't a native speaker of English, so those mocking you are just either stupid or willfully ignorant.
That said, I'm pretty sure Watters' World is satire. If it's not, it really should be. Like the onion.
A) have you read Keeler's posting history? sadly, he was serious.
B) you wouldn't recognize "x" if one bit you in the ass is a long held phrase in the english language.