This was my thought as well. The comparison isn't exact, but this feels like a War on Drugs situation: you're never going to stamp out all spying, and as you try, a lot of innocent (or at least non-harmful) people will get swept up in the process and their lives destroyed.

Now, I think policing espionage is more valuable than policing drugs, and the dynamics certainly all aren't the same. But I think the bar for making espionage accusations -- just the accusations themselves -- needs to be much higher than it is.