Exactly. "Oops" when you're testing nuclear weapons would simply be a different yield than expected. I imagine the USAF radioisotope analysts (if that's still

Exactly. "Oops" when you're testing nuclear weapons would simply be a different yield than expected. I imagine the USAF radioisotope analysts (if that's still done these days, expect it might be impossible with underground testing) could possibly detect less-than-complete fusion. But you've got to screw up pretty badly to have a static nuclear weapon test misfire.