Merry flippin’ Christmas.

Today, on Christmas Eve, the UN’s Arms Trade Treaty takes effect, giving Americans a lump of coal in their stockings this holiday season.

The ATT is a bad idea that keeps getting worse. In theory, it’s about stopping the sale of guns to terrorists and mass murderers. But in practice, it’s about preventing Israel from defending itself, allowing left-wing activists to dictate U.S. foreign policy and giving anti-gun advocates a leg up.

The treaty takes effect 90 days after it’s ratified by 50 nations. That happened on Sept. 25, so the ATT enters into force on Christmas Eve. That’s not likely to be a coincidence: Treaty advocates pretend the ATT is a present of peace to the world, so the timing suits their propaganda perfectly

The administration made a serious mistake when it signed the ATT in 2013, and since then, it’s been heavily criticized in the…