Shinzo Abe's flight home from Quebec City was as lonely as they get.
Japan's prime minister had long known that his one-time pal Donald Trump would be leaving him out of the historic tete-a-tete with Kim Jong Un in Singapore.
But what must have been a shock was the scale of the damage that the U.S. president inflicted on Abe and on other partners in the Group of Seven, the premier summit of the free world.
Early on, Abe bet big on the mercurial U.S. president, only to get trumped as Trump tore up the cards of traditional diplomacy.
No international forum is more vital to Tokyo than the G-7. A decade ago, when many thought the Group of 20, a much larger association that includes China, India and other developing countries, should take the lead, Japan lobbied to preserve the G-7 as the top framework.
Tokyo worked hard to retain its unique role as the Western economy of the East, and is loath to give up that status regardless of China's rapid ascent.
So, Abe has some explaining to do as Trump does his worst to blow up Tokyo's preferred pecking order. Headlines about Trump' tantrum in Quebec, where he rejected the G-7 communique and verbally attacked counterparts, were bad enough. But there was also a telling picture from the scene that dramatizes the point -- and exposes Abe's vulnerability.
Arguably, no G-7 gathering has produced a more cantankerous photo: Trump sits alone, arms crossed, surrounded by world leaders pleading their case. To Trump's right, Abe stands, arms folded seemingly distancing himself from the argument, perhaps in solidarity with his bromantic partner. Not a great look for Japan, considering how Abe's investment in Trump is going awry, in ways that dent Japan's clout.
Abe's Trump Tower sprint in November 2016, nine days after Trump's shock victory, was seen as a win in Tokyo at the time. Being the first world leader to pay tribute to the president-elect, pundits thought, would preserve the U.S.-Japan military alliance and afford Tokyo preferential trade treatment.
Japan's leader has been wrong at every turn. From rejecting the Trans-Pacific Partnership to tariffs on steel, aluminum and, perhaps, cars, to rewarding Kim with a summit, Trump has ignored Tokyo's interests.
In Singapore, Trump failed to deliver on what Abe most wanted: any sign North Korea would reopen talks about Japanese abducted decades ago. It did not warrant even a fleeting mention in the Trump-Kim "agreement," which could dent Abe's already feeble approval ratings at home.
Tokyo is left with an unpalatable choice: stick with a Trump administration treating tyrants better than allies or risk its wrath as it distances itself. The Trump presidency will end at some point. Japan will then be left with restoring face among G-7 powers skeptical of Abe's Trump embrace. Europe, remember, has the European Union. That goes, too, for the U.K., no matter what today's Brexit drama portends, as London will retain close ties with the continent. The U.S. and Canada can doubtless figure out how to coexist within North American institutions.
In the age of China, though, the G-7 is Japan's trump card, in terms of global influence. Asia has no real geopolitical grouping. Tokyo's inclusion in the ultimate members-only club also is closely tied to its quest to become a permanent member of the United Nations Security Council. Abe would be wise to focus more on that prize than staying in cahoots with a destructive U.S. president.
Take, for example, Trump's campaign to give Russian president Vladimir Putin a seat at the G-7 table -- the geopolitical equivalent of an arson attack.
Now, Britain, Canada, France, Germany, Italy, Japan and the U.S. all welcomed Russia into the fold back in 1998. Not because of its economic heft, of course. But because of concern about propping up a failing nuclear superpower. Putin made the G-7 regret it when he annexed Crimea, running afoul of international law. Only somebody as cavalier with the law as Trump would propose ignoring this brazen crime.
Here is a better idea: the U.S.'s G-7 partners should call Trump's bluff by proposing adding China and India instead. The much-larger G-20 is a fine as a diverse grouping representing the global economy. But since its inception in 1999, it has proven too unwieldy and unresponsive to guide global policy.
While Abe might object, adding China to the G-7 is a no-brainer. With all due respect to Canada and Italy, it is time to send one of them packing. China is the second-biggest economy, the No. 1 trading nation, the largest holder of currency reserves, the top polluter and increasingly the banker to developing nations everywhere. No challenge can be tackled without Beijing's input. Adding India, the seventh-biggest economy, as well would help the G-7 dispel its elitist reputation. It would also give Asia the role its economic clout deserves at the top table.
The argument for preserving the same lineup dating back to 1976 is that China is not enough of a market economy. That is fair. But now that Trump is dragging the U.S. away from free market principles, that line loses credibility. Adam Smith, after all, might give President Xi Jinping's capitalism higher marks than Trump's grievance-based protectionism.
Abe's lonely week warrants deep reflection. His estrangement from Trump has security as well as economic consequences. Trump's glad-handing a member of the murderous Kim clan may have made Japan less safe. Kim, weirdly, received a rock star's welcome in Singapore. Shout-outs and applause from onlookers, jovial selfies with local diplomats. Desperate to win a concession, any concession, Team Trump may accept an end to Kim's long-range missile program and move on. That still leaves Pyongyang plenty of medium-range weapons capable of hitting Japanese soil.
The question now is what Trump does with his former best friends. Things have gotten so heated that he is calling prime minister Justin Trudeau's Canada, with which the U.S. enjoys a trade surplus, a bad actor. It may be only a matter of time before Trump focuses on the U.S. deficit with Japan and lashes out accordingly at Abe.
Trump will exit the scene at some point. In the meantime, Abe must pivot to deepening relationships closer to home. He should be mending fences with China and South Korea, while increasing Japanese involvement in south east Asia, where, for example, a post-election Malaysia is looking for new opportunities. The key lies in reducing exposure to a White House that acts as if it could not care less about Tokyo's economic and security priorities.
William Pesek is a Tokyo-based journalist and author of "Japanization: What the World Can Learn from Japan's Lost Decades." He has written for Bloomberg and Barron's.