We also know pre-9/11 how common it was (non-existent).
We also know that they consistently fail audits. Though they've gotten better! Most recently they only failed ~75% of the time at detecting things auditors were trying to smuggle in, instead of the prior 95%!
So, yeah, by itself it doesn't. But we have enough data to make a pretty solid eval.
If they see a country isn't up to their standard, I think they either show up to implement it for flights headed to the US or at least consult with the nation.
> The TSA has never found a bomb.
Perhaps I'm missing something, but I don't understand how that supports your statement.
I can't believe he'd be dumb enough to try to bring this on an airplane. It'd make way more sense to ship them to w/e destination.