President Donald Trump repeated a slew of false claims to an international audience at the annual NATO summit:

The overwhelming majority of captured Islamic State fighters are from Iraq and Syria. They are not, as Trump claimed, “mostly from Europe.”

Although about half of the territory once held by the Islamic State was regained under President Barack Obama, Trump again wrongly claimed that, “When I came in, it was virtually 100%. And I knocked it down to zero.”

The U.S. trade deficit with the European Union has gone up under Trump, contrary to his suggestion that he had reduced it “fairly rapidly.” And as he has done many times, he inflated the amount of that trade deficit.

The president wrongly claimed that other NATO member countries’ spending on defense was “heading down” three years ago. That spending went up in 2015 and 2016. And he claimed countries that spent a low percentage of their GDP on defense were “delinquent.” They don’t owe NATO, or other countries, any money....