There's a fair dose of racism involved, just as there was with the very similar hysteria over Japanese investment in the 1980s.
As you correctly point out, there is a hysteria about Russians at the moment, as well. I think the US is primed for this because of the long history of anti-Russian propaganda during the Cold War.
When it comes to China, I see all sorts of extra negative characterizations of Chinese people coming into play. I've seen threads here on HN which people go on about how Chinese students are cheaters, and how Chinese culture promotes cheating. That's just an outrageous and ignorant characterization of Chinese culture, and I do think it represents a type of widespread prejudice.