US President Donald Trump says he plans to ban the Chinese-owned video app TikTok with Microsoft said to be in talks to take TikTok’s US operations over. US officials are currently looking into the possibility that China can access user data collected by the app. An outright ban would come as a blow to TikTok's millions of fans, but its exploding popularity has also raised red flags. The plan comes on the heels of tit-for-tat consulate closures in Houston and Chengdu. Is TikTok a threat to US national security?