National security is the dominant theme of lawmakers’ questions.

Lawmakers on the House Energy and Commerce Committee demanded accountability and transparency from TikTok chief executive Shou Chew during a five-hour hearing on Thursday, accusing the company of maintaining ties to the Chinese government and have adverse effects on children and adolescents.

TikTok, which has 150 million users in the United States, has come to represent the growing divide between the United States and China in technological leadership and national security – its parent company, ByteDance, is Chinese. The app has become a battleground in a tech cold war between the two countries, with US threats to ban TikTok a reminder of how China has long blocked many US platforms.

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