There are simply too many talents coming and working in the States in the past. So Americans do not care. Now more and more talented foreigners choose to not to come / return. Many of them get much higher social status and even make more $$$ in their home countries. So this issue will be less and less relevant to those foreign talents, arguably the exact people US should retain/attract for its own benefits.
Such trends actually already exists for some time, even though it has not been noticed. Taking Mexicans as an example. Almost everybody and all media are talking about incoming Mexicans. But if we really think about this, at least, I have noticed that there actually not many educated Mexicans around in US. I think it is fair to say that, compared with Chinese and Indian alike, it will be much easier for educated Mexicans to come to US. If these people are not coming, it might be because they feel they are better off back in Mexico. If Mexicans prefer to stay home, sooner or later, vast majority of talented Chinese/Indian will do the same. Then let's imagine a Silicon Valley without Chinese/India, Quant / IT / Risks etc team without Chinese / Indian on Wall St.
I personally think US is repeating the same mistake Chinese made 300 years ago.