The leaders reaffirmed their “ironclad commitment” to NATO’s collective defense clause, Article 5. In recent years, Trump had sowed seeds of doubt about whether the U.S. — NATO’s most powerful member — would come to the aid of any ally under attack.

There were unexpected moments of levity among the momentous decisions on raising spending to levels not seen since the Cold War.

NATO allies on Wednesday agreed to more than double their defense spending target from 2% of gross domestic product to 5% by 2035, in the most decisive move from the alliance in over a decade