The Republican candidates’ individual fortunes have gyrated this campaign season, but they have one target in common: Europe. Not a day on the trail passes without Mitt Romney, Rick Santorum or Newt Gingrich knocking Europe’s fiscal fecklessness and its “socialist” welfare system.

Rick Santorum addresses the Alabama Republicans forum in Birmingham, March 12, 2012.(Reuters/Marvin Gentry)

European leaders have tended to shrug it all off—until Mr. Santorum took a poke at Holland.

Lately the conservative former Pennsylvania senator has been claiming that Dutch government-run hospitals involuntarily euthanize old sick people in order to save money. In fact, he said, elderly people killed off by hospitals for budget purposes account for 5% of all deaths in the Netherlands.

“Elderly people in the Netherlands don’t go to the hospital. They go to another country because they’re afraid because of budget purposes they won’t come out of that hospital,” he said last month at a public forum in Missouri. It’s so bad that old people wear a bracelet that says, “do not euthanize me,” he told the audience, as some gasped in shock.

None of this is true, says the Dutch government, some members of which are demanding that Mr. Santorum correct the record…