Member states largely agreed to a U.S. demand to boost defense spending to 5% of gross domestic product. Trump, who once derided the alliance as a "rip-off," said his view had changed, while a budding bromance blossomed between him and Rutte, who compared the U.S. president to a stern "daddy" managing his geopolitical underlings.

For U.S. President Donald Trump, Vladimir Putin is a man looking for an off-ramp to his bloody three-year assault on Ukraine.