President Donald Trump used a NATO summit in Ankara to put Greenland back at the center of U.S. foreign policy.

After several quiet months, Trump revived a dispute with Denmark, recasting the Arctic island as a security necessity.

What Happened?

Speaking alongside NATO Secretary General Mark Rutte, Trump accused allies of failing Washington on Arctic security and said the U.S. had made a historic mistake by returning control of Greenland to Denmark after World War II.

"We took Greenland and then, stupidly, we gave it back," Trump said.