Well we got along quite well and built Silicon valley before any of you arrived. I am sure we’ll manage somehow,

https://www.quora.com/Can-the-USA-survive-without-high-skilled-foreign-worker-under-an-H-1B-visa

“It is very sad that immigration workers contribution to American economy has been hyped and overrated. No doubt, American economy will suffer, if tomorrow the immigration policy is abolished.

The american industry does not want to lose out on attracting on some of the sharpest brains from outside of US to maintain the cutting edge technology and be in the frontiers of emerging technological revelution.  It is with this idea, that the immigration policy was put in place,

But in the bargain so many things happen. Not so much dearth of talent is there in US.  Under the garb of immigration policy, some not too sharp brains also get their lease. In the name of quota and lottery, some best brains also get rejected”.