If they move "all of the jobs back to the prc," then that means that someone else will provide the jobs over HERE. (They can't exactly rip out all of the fiber and take it to China--so any move as you describe would amount to abandoning their infrastructure investment.)
As for your fear of the ChiComs being "able, eventually, to get a better understanding of our electronic communications systems," please note that we use radio quite extensively in the military, and that those signals can be intercepted very easily by ANYONE, including the ChiComs, and that they can gain a better understanding of our electronic communications systems much more easily than they would with this deal--because the aiwaves cost them nothing to run.