Cite as: 603 U. S. ____ (2024) 9 Opinion of the Court II NetChoice chose to litigate these cases as facial challenges, and that decision comes at a cost. For a host of good reasons, courts usually handle constitutional claims case by case, not en masse. See Washington State Grange v. Washington State Republican Party, 552 U. S. 442, 450–451 (2008). “Claims of facial invalidity often rest on speculation” about the law’s coverage and its future enforcement. Id., at 450. And “facial challenges threaten to short circuit the democratic process” by preventing duly enacted laws from being implemented in constitutional ways. Id., at 451. This Court has therefore made facial challenges hard to win. That is true even when a facial suit is based on the First Amendment, although then a different standard applies. In other cases, a plaintiff cannot succeed on a facial challenge unless he “establish[es] that no set of circumstances exists under which the [law] would be valid,” or he shows that the law lacks a “plainly legitimate sweep.” United States v. Salerno, 481 U. S. 739, 745 (1987); Washington State Grange, 552 U. S., at 449. In First Amendment cases, however, this Court has lowered that very high bar. To “provide[ ] breathing room for free expression,” we have substituted a less demanding though still rigorous standard. United States v. Hansen, 599 U. S. 762, 769 (2023). The question is whether “a substantial number of [the law’s] applications are unconstitutional, judged in relation to the statute’s plainly legitimate sweep.” Americans for Prosperity Foundation v. Bonta, 594 U. S. 595, 615 (2021); see Hansen, 599 U. S., at 770 (likewise asking whether the law “prohibits a substantial amount of protected speech relative to its plainly legitimate sweep”). So in this singular context, even a law with “a plainly legitimate sweep” may be struck down in its entirety. But that is so only if the law’s unconstitutional applications substantially outweigh its constitutional ones. So far in these cases, no one has paid much attention to