Nobody in the IC believes allies aren't constantly spying on each other. Germany and France are notorious for doing it to support their state industries. Like it or not, in the intelligence arena, the US and Germany are rivals.

I'm sure that's happened, but there's a reason the EQ dump included lots of vulnerabilities for Chinese products nobody in the US deploys.

"Enemy" is a weird word ("adversary" is probably better), but however you slice it: NSA's mission includes real ones.

Their tasking, though, is to break into foreign ones. They see breaking into domestic ones as necessary to do that (and I can see why they might feel that way, even if I don't like the result), but I don't believe it's part of their core mandate.