WASHINGTON —President Donald Trump’s signature slogan — “America First” — lately has gotten a tweak from administration aides eager to show that his nationalism is not at odds with the United States’ traditional global leadership role. Their new version: “America first does not mean America alone.”

Yet America was undeniably alone as Trump on Saturday departed the annual summit of the Group of 20 leaders in Hamburg, Germany. With the leaders’ final statement, it was evident that Trump’s prioritization of American self-interest — on environmental agreements, trade, migration and more — left him, and thus America, often in unfamiliar isolation.

After two days of cordial smiles and handshakes, Trump expressed satisfaction with the summit. Even so, he was alone among leaders of the world’s major economic powers in dissenting from its resolution affirming the Paris climate accord. And while he has threatened to abandon trade deals and penalize countries for what he sees as unfair trade practices, particularly on steel exports, the summit’s closing declaration affirmed support for open markets and fighting protectionism.

After the more exclusive Group of 7 summit in May, German Chancellor Angela Merkel had described the meeting as “six against one” — the one being the United States. As she closed the G-20 gathering that she hosted, Merkel again singled out the United States.

In a news conference, Merkel said she “deplores” America’s decision to walk away from the Paris climate agreement and, despite Trump’s comments, does not believe the administration is open to renegotiating the terms agreed to among more than 190 nations to mitigate the effects of climate change.

Merkel, as she has before, called on European countries to step into the vacuum that Trump is leaving on the world stage.

“We as Europeans have to take our fate into our own hands,” she said.

The new French president, Emmanuel Macron, who will host Trump this week in Paris to mark Bastille Day, echoed Merkel. “The world has never been so divided,” he said.

In another break from past decades, the United States seemed closer to Russia — in goodwill if not on many issues — than with traditional allies such as Germany and France after Trump’s genial tete-a-tete with President Vladimir Putin on Friday.

Trump’s meeting with Putin, lasting more than two hours, was his longest with any leader. He raised Americans’ concerns over Russian election meddling, according to aides, but the two presidents decided to put the matter behind them and move on to discuss how they can address their differences over Syria, Ukraine and North Korea.

Unlike many other leaders, Trump didn’t hold a news conference at the conclusion as Americans presidents typically have done. Putin, in his meeting with reporters, denied again — as he did to Trump on Friday — that Russia interfered in the U.S. election, and said he thinks that Trump accepted his face-to-face denials.

White House officials declined to challenge Putin’s view that Trump accepted his denials when questioned on Air Force One en route back to Washington.

Trump “will be happy to make statements himself” about his meeting with Putin, Treasury Secretary Steven Mnuchin said.

He and Trump’s top economic adviser, Gary Cohn, were sanguine about the summit’s results, and singled out as constructive the leaders’ discussions about dumping of cheap raw materials, limiting migration, and cracking down on terrorist financing.

“These things are never easy — to get 20 of your friends to agree where to have dinner tonight is really hard — but I thought the communique came together pretty reasonably,” Cohn said.

For nearly three-quarters of a century, since World War II, the United States has been the pre-eminent leader in championing open markets and forging a multilateral system of rules to resolve international disputes.

Trump has repeatedly signaled his skepticism of multilateral institutions like the European Union and forums like the G-20. In Hamburg, rather than using the conference to build broad consensus around his populist ideas, he spent most of his time in private one-on-one discussions with leaders.

The president often retreated from the group’s larger sessions in favor of such bilateral meetings

Trump and the other leaders of the G-20 signed off on a joint statement that was seen as an accomplishment given the sharp differences and acrimony.

“We have a G-20 communique, not a G-19 communique,” said one EU official after all-night negotiations to finesse the divisions. But the language on climate change, at least, made plain that the statement was in fact a G-19 communique, with the U.S. alone in opposition.

Despite friction with Merkel, Trump thanked her Saturday for hosting the summit even as protesters clashed violently with police at times.

“You have been amazing, and you have done a fantastic job,” he said.

brian.bennett@latimes.com