Genuine question: If China's priorities are in the right order, then why is the US giving the social network so much attention, going so far as to label it as a

Genuine question: If China's priorities are in the right order, then why is the US giving the social network so much attention, going so far as to label it as a "national security threat" (whatever that means these days)? Also wouldn't that open US services like facebook and snapchat to the similar treatment by other governments? Why would the US jeopardize their industry like this? Something doesn't add up.