The kind of interception abilities they're worried about come from intentionally introduced flaws in the software (or, less commonly, in an ASIC or similar). Th

The kind of interception abilities they're worried about come from intentionally introduced flaws in the software (or, less commonly, in an ASIC or similar). This is why cisco equipment can be manufactured in china and not cause worries (to the US) but the counterfeit cisco gear is a serious concern. Additional bugs or chips that didn't belong are relatively easily detected - nation states play at things like intentionally weakened random number generators or side channel leakage.