So after Biden claimed that Erdogan had acknowledged fault in enabling the flow of foreign fighters across the Turkish border, it was inevitable that a firestorm would ensue.

Biden swiftly responded on Saturday to a demand by Erdogan for an apology, saying he regretted the criticism of Turkey and also a suggestion that other American allies had helped facilitate the rise of the extremist Islamic State in Syria.

“The vice president apologized for any implication that Turkey or other allies and partners in the region had intentionally supplied or facilitated the growth of ISIL or other violent extremists in Syria,” the White House said in a statement, using an acronym for the Islamic State.