At least 18 states, all led by Republican governors, have banned staffers’ use on government devices of the social media app TikTok over concerns about the possible security risks posed by the Chinese-owned company. They say the app can be used to collect data from users’ devices, which the Chinese government could then access.

Some states have gone even further, banning apps and products such as WeChat, QQWallet, and AliPay from other Chinese companies.

In Maryland, Republican Gov. Larry Hogan authorized his chief information security officer, Chip Stewart, to issue such an emergency directive. The directive prohibits…