Earlier quoted context omitted.
What exactly does this incident have to do with counterintelligence? I think you are using that word incorrectly. I also don't understand what those linked incidents have in common. Sure, the US military isn't invulnerable and there is always risk associated with combat.
I think they are saying the US systematically underestimates the enemy's capability so it probably wasn't actually that surprising an F117 was downed.
I also grew up thinking a Stealth Fighter could never be shot down. It's invisible. No way.