After he struggled to condemn a white supremacist terrorist attack in the United States, reluctantly condemned it, and then pivoted back to the idea that not every participant in a neo-Nazi rally that ended with a woman’s murder was necessarily bad, a deadly terrorist attack in Barcelona offered President Trump the more comfortable terrain of talking about Islamic terrorism.

Specifically, he suggested on Twitter that the long-dead American Gen. John Pershing has the fix that the world needs today.

Study what General Pershing of the United States did to terrorists when caught. There was no more Radical Islamic Terror for 35 years! — Donald J. Trump (@realDonaldTrump) August 17, 2017

This is a reference to a story Trump has told in the past about efforts undertaken by the United States to subdue an insurgency in the Philippines. The United States took control of the islands after a brief war with Spain in 1898, and then fought a three-year war against the locals to secure control over it. But localized unrest continued in some areas, and Pershing served as governor of Moro Province, which is predominantly Muslim, between 1909 and 1913 before going on to his better-known career as the leader of American military forces in World War I.

At a February 19, 2016, rally in South Carolina, Trump offered this account:

They were having terrorism problems, just like we do. And he caught 50 terrorists who did tremendous damage and killed many people. And he took the 50 terrorists, and he took 50 men and he dipped 50 bullets in pigs’ blood — you heard that, right? He took 50 bullets, and he dipped them in pigs’ blood. And he had his men load his rifles, and he lined up the 50 people, and they shot 49 of those people. And the 50th person, he said: You go back to your people, and you tell them what happened. And for 25 years, there wasn’t a problem. Okay? Twenty-five years, there wasn’t a problem.

After Trump told this story, Louis Jacobson of PolitiFact looked into it with eight historians, all of whom were deeply skeptical that it ever happened. The notion that pig’s blood was used as an anti-Muslim weapon appears to derive from a 1939 Gary Cooper movie and a single letter written in 1960.

And of course while observant Muslims avoid eating pork products, they’re not vampires who can only be killed by special bullets. There’s no precept of Muslim doctrine that would suggest being shot at with pig blood–soaked bullets would imperil one’s immortal soul. In the bigger picture, unrest in the Philippines didn’t actually taper off while Pershing was governor — let alone stop for 25 years. Plus, you can’t execute suicide attackers anyway.

So while the story seems to appeal to Trump’s predilection for the grotesque — and appears to revive the direct advocacy of torture and war crimes that were a hallmark of his presidential campaign — all indications are that it’s false and completely nonsensical.