Anything the government uses that needs to be hardware-secure (like Secret or Top Secret network devices) are either manufactured in small batches in a secure location or it's totally airgapped so that any "additions" don't matter. Let the Chinese have their extra chip installed anywhere they want and you wouldn't get anything out of it anyways, in that situation.

The real problem is for stuff connected to the non-secure internet, like banks, industry, personal info, healthcare, etc.