But the catalytic converter itself was fabricated in the US; only the raw materials for the catalytic converter didn't.

(I'm using platinum ingot since that's how I'm assuming you'd buy a lump of platinum metal. If this is not correct, substitute for whatever the thing is you'd actually buy from somebody like Rio Tinto. I'd have used the platinum ore directly, but my understanding is that it generally is produced as a byproduct of other metal refining.)

Which means if the US went to war with X, you can’t make cars. That’s a critical distinction when talking about defense contractors.