President Trump this week mused about barring the popular short video app TikTok, which has reportedly been downloaded over 165 million times in the U.S.

His comments came a day after Secretary of State Mike Pompeo floated such a ban as part of an escalating trade war with China. TikTok is owned by Beijing-based ByteDance and critics warn that the Chinese government can spy on its users.

But while the Trump Administration has talked on “banning” TikTok, it’s unclear how exactly such a ban would be carried out. Any sort of decree ordering people not to use the app would likely be unconstitutional—and would be met with resistance from millions of Americans, especially young ones, for whom TikTok has become a form of cultural expression.

According to lawyers at the Electronic Frontier Foundation (EFF), a digital rights group, Trump’s pledge to ban TikTok may reflect bluster more than any sort of coherent policy.

Kurt Opsahl, general counsel of EFF, says the White House could attempt tactics such as banning federal workers from using TikTok or preventing federal money from being spent on the app. A more aggressive approach, he suggests, could involve using export regulations to require U.S. companies to obtain a license to do business with TikTok.

For practical purposes, such a licensing requirement would likely target Apple and Google, whose app stores are where the vast majority of people get the TikTok app in the first place.

But it’s unclear if export regulations—which the U.S. has successfully employed to limit Chinese hardware manufacturers like Huawei and ZTE—could apply to something like an app. The use of such regulations typically entail barring a U.S. company for exporting chips or other technology, and Apple and Google don’t appear to do anything of the sort in providing their app store. Moreover, TikTok has significant U.S. based operations and could argue export regulations don’t apply to them.

Any proposal to “ban” TikTok is further complicated by the fact that the app is a type of software code, and courts have found that publishing and using code can be protected by the First Amendment.

Mitch Stoltz, a senior attorney at EFF, points to a recent case in which the Ninth Circuit of Appeals ruled the federal government could not use regulations related to weapons exports to force a cryptography researcher to submit his code for license and review. This suggests any attempt to ban TikTok could face legal challenges invoking free speech.

All of this doesn’t mean attempts to limit TikTok will fail. Senators of both parties have called for investigations of the app’s ties to China, and other countries—notably India—are taking measures to ban the app. But in the short term, Americans can feel confident TikTok is not going away anytime soon.

“We could spend a lot of time spinning our wheels trying to anticipate ways that the Administration could try to ban, but it still remains their job to figure out what they meant, and explain how it is a lawful and constitutional exercise of executive power,” says Opsahl.