I think its more normal to have a "moderate view on China" than you would assume if you only interact with other people online, or via reading newspapers. Normal Americans don't even see their own government as being their business (with good reason, since democratic inputs are not connected to governmental decision-making), let alone some country on the other side of the world where they'll never go, or likely even meet someone from.

I suspect the modal view on China among Americans is just nothing -- they've never even thought about it. We'll never get a poll that confirms this because asking the question at all clouds the answer.