With heads of state taking care not to poke Mr. Trump, Donald Tusk, president of the European Council, has emerged as the Continent’s most prominent and pointed critic of the president.
Mr. Tusk, one of the leaders of the European Union, has no formal role in NATO, but the two groups have a large overlap in membership. On Tuesday they signed a statement of cooperation.
Mr. Tusk has made clear that he is paying close attention to the summit, he has a megaphone, and he’s not afraid to use it. Tweaking and refuting Mr. Trump, often slyly and sometimes quite directly, his comments are widely seen to reflect what other European leaders are thinking but are unwilling to say publicly.
The United States “doesn’t have and won’t have a better ally than EU,” whose members combined spend more on defense than Russia, he tweeted on Wednesday. “I hope you have no doubt this is an investment in our security.”
In June, after Mr. Trump’s angry exit from the Group of 7 summit and his broadside at Justin Trudeau, the Canadian prime minister who played host to that meeting, Mr. Tusk tweeted, “There is a special place in heaven for @JustinTrudeau.”
He used sharper language in May, after Mr. Trump withdrew from the Iran agreement and announced trade sanctions. Mr. Tusk tweeted, “with friends like that who needs enemies.”
Idle thumbs? Meeting rooms will be a Twitter-free zone
Mr. Trump enjoys sending Twitter barbs at his adversaries, but he will be restrained during the NATO summit meeting.
In NATO’s new building, in the massive high-tech meeting room, no mobile phones are allowed — not even for a president. Even if they were permitted, they probably would not work, because NATO jams signals in the building to prevent eavesdropping or hacking.
So at least for the hours he is with other leaders, Mr. Trump will be under a cone of silence.
Mr. Trump will have to wait until he’s outside the NATO building to get to his Twitter account in order to reassure his many followers that he remains the @realdonaldtrump. — Steven Erlanger
A show of solidarity with Ukraine
NATO leaders are set to meet with their Ukrainian counterparts on Thursday to show solidarity with Kiev, in the face of the Russian annexation of Crimea in 2014, and Moscow’s continuing military support of rebels in eastern Ukraine.
The meeting is pointed reminder from the West of the principle that one nation should not violate the territorial integrity of another, before Mr. Trump’s meeting with Mr. Putin in Finland. Talks on resolving the dispute in Ukraine have essentially stalled, and Western diplomats do not expect significant progress on the issue at the Helsinki summit meeting.
NATO leaders are also to meet with the leaders of Georgia on Thursday, in a similar show of support for Tbilisi against Russia, which has occupied parts of Georgia since 2008.
Ukraine and Georgia will be invited to discuss their progress in security and defense overhauls and their cooperation with NATO.
Membership is a different matter, however. In 2008, at a summit meeting in Bucharest, NATO promised both Ukraine and Georgia eventual membership in the alliance, infuriating Mr. Putin. Those plans have been put on hold. — Steven Erlanger