President Trump has spent the week setting the bar extremely low for his high-stakes U.S.-Russian summit on Friday in Alaska. Hardly anyone expects him to make much progress in halting the fighting between Russia and Ukraine, given how far apart their views of the conflict are.

But those two warring countries do seem to agree on at least one thing. Merely meeting with Mr. Trump is a big win for President Vladimir V. Putin, bringing the Russian leader out of a diplomatic deep freeze and giving him a chance to cajole the American president face to face.

“Putin’s visit to the U.S.A. means the total collapse of the whole concept of isolating Russia. Total collapse,” Kremlin-controlled television crowed after news of the hastily arranged summit broke last weekend.

For Russia, “this is a breakthrough even if they don’t agree on much,” said Sergei Mikheyev, a pro-war Russian political scientist who is a mainstay of state television.

President Volodymyr Zelensky of Ukraine, iced out of the Alaska talks about his own country’s future, has come to the same conclusion, telling reporters on Tuesday: “Putin will win in this. Because he is seeking, excuse me, photos. He needs a photo from the meeting with President Trump.”

But it is more than a photo op. In addition to thawing Russia’s pariah status in the West, the summit has sowed discord within NATO — a perennial Russian goal — and postponed Mr. Trump’s threat of tough new sanctions. Little more than two weeks ago, he vowed that if Mr. Putin did not commit to a cease-fire by last Friday, he would to punish Moscow and countries like China and India that help Russia’s war effort by buying its oil and gas.