Facts Tell: Who is actually threatening U.S. national security?

On August 6, U.S. President Donald Trump signed a pair of executive orders, setting a 45-day timer for banning popular mobile apps TikTok and WeChat in the country. Trump said these popular social media apps were threatening American "national security, foreign policy and economy." So, how can TikTok, a platform where teenagers post memes and lip-sync videos, threaten U.S. national security? By banning TikTok and WeChat, is the U.S. government really protecting national security or is it something else?