So first, support your claim that Chinese spy more. Is it really that hard?
Second, even if that is true, the second part is not necessarily true. For example, white people are far more likely to be members of the KKK than any other race. Does that mean that white people deserve additional scrutiny because of it? No, because even though the relatively probability is much higher, the absolute probability is still negligible.
Let's say, for the sake of argument, that Chinese people spy at four times the average rate. If the average rate was 20% and the Chinese rate was 80%, yeah, clearly you should be checking into that pretty hard. On the other hand, if the average rate was 0.001% and the Chinese rate was 0.004%, you're just wasting resources if you think that justifies scrutiny of all Chinese.
That's not my point. My point is that everyone here is enjoying their self-righteous anachronistic indignation & kibbitzing & moral superiority without even reaching the basic level of discussion of asking 'are Chinese immigrants more likely to be spying for China than regular scientists and so additional scrutiny warranted?' It's not that anyone has presented numbers or evidence - they don't even realize that they need to.
It's like if everyone was going around accusing me of racism and being an idiot and a Nazi and a Stormfront user (oh wait!); yes, maybe I have not presented a hard census of how many Chinese immigrants were working in sensitive programs and became suspected of being spies, but frankly, this discussion has much bigger problems than that.