TikTok commands the attention of 150 million American users. That's its best defense yet against Biden's threat of a ban.

• TikTok officially has 150 million monthly active users in the US, the company says.
• The app's popularity with younger voters makes a ban politically sensitive, experts say.
• TikTok's user numbers could ultimately be its best defense. It's now a routine for 45% of the US.

TikTok officially has 150 million monthly active users in the US, the company confirmed this week. That means any effort to ban it could face stiff resistance after the app has become part of the routine of 45% of the country.