While Trump got what he wanted at the annual meeting, tailor-made for him, his NATO allies will be relieved that he committed to the military alliance's fundamental principle of collective defence.
Trump told a press conference that "we had a great victory here," adding that he hoped that the additional funds would be spent on military hardware made in the United States.
However, he threatened to punish Spain after Prime Minister Pedro Sanchez declared it could meet its commitments to NATO while spending much less than the new target of five per cent of GDP.
"I think it's terrible. You know, they (Spain) are doing very well ... And that economy could be blown right out of the water when something bad happens," Trump said, adding that Spain would get a tougher trade deal from the US than other European Union countries.
In a five-point statement, NATO endorsed the higher defence spending goal - a response not only to Trump but also to Europeans' fears that Russia poses a growing threat to their security following the 2022 invasion of Ukraine.
The 32 allies' brief communique added: "We reaffirm our ironclad commitment to collective defence as enshrined in Article 5 of the Washington Treaty - that an attack on one is an attack on all."
Asked to clarify his own stance on Article 5, Trump said: "I stand with it. That's why I'm here. If I didn't stand with it, I wouldn't be here."
Trump had long demanded in no uncertain terms that other countries step up their spending to reduce NATO's heavy reliance on the US.
Despite an appearance of general agreement, French President Emmanuel Macron raised the issue of the steep import tariffs threatened by Trump, and the damage they may do to transatlantic trade, as a barrier to increased military spending.
"We can't say we are going to spend more and then, at the heart of NATO, launch a trade war," Macron said, calling it "an aberration".Â
He said he had raised it several times with Trump.
NATO Secretary General Mark Rutte, who hosted the summit in his home city of The Hague, said NATO would emerge as a "stronger, fairer and more lethal" alliance.
The former Dutch prime minister said Trump deserved "all the praise" for getting NATO members to agree on raising defence spending.
Asked by a reporter if he had deployed excessive flattery to keep Trump onside during the summit, Rutte said the two men were friends and judgment of his approach was a matter of taste.
The new spending target - to be achieved over the next 10 years - is a jump worth hundreds of billions of dollars a year from the current goal of two per cent of GDP, although it will be measured differently.
Countries pledged to spend 3.5 per cent of GDP on core defence - such as troops and weapons - and 1.5 per cent on broader defence-related measures such as cyber security, protecting pipelines and adapting roads and bridges to handle heavy military vehicles.
