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Shinzo Abe just wants everyone to get along. The Japanese prime minister, host of the Group of 20 summit of world leaders this week in Osaka, Japan, has suggested he hopes to use the gathering to highlight unity among the global community, rather than division.

“We want to make it a meeting that focuses on where we can agree and cooperate rather than highlighting differences,” Abe said during a recent media appearance. “The global situation is severe. If the G-20 breaks apart, say, in the field of the economy or security, it will be over."

There’s a major problem with that plan, of course: The world isn’t united right now. And President Trump, Abe’s golfing buddy and the source of much of that global division, is unlikely to suddenly start building bridges while he’s in Osaka.

This will be the second time in two months that Abe has hosted Trump. In late May, the American president visited for the imperial succession of Japan’s new emperor, Naruhito. That visit was full of tradition and tradition-breaking designed to woo Trump (the American leader was allowed to sit on a chair during a sumo match, generally a no-no in the conservative sport).

That Trump would make the journey across the Pacific twice for Abe suggests that the Japanese leader’s persistent quest to be the U.S. president’s greatest foreign ally is bearing some fruit.

However, Abe knows as well as anyone just how tough it can be to be an American ally under Trump, who’s not afraid of a little friendly fire. On Tuesday, Bloomberg News reported that Trump had mused privately about ending a 60-year-old defense agreement with Japan.

The next day, only hours before boarding a flight to Japan, Trump publicly confirmed the report, suggesting the agreement was lacking in reciprocity. “If we’re attacked, Japan doesn’t have to help us at all,” Trump said during an interview with Fox Business.

But Trumpian disruption is unlikely to be confined to Japan’s postwar military politics this week. While Tokyo has set an ambitious and lengthy G-20 agenda, including global problems such as climate change and issues affecting women in the workforce, the discussion of the event probably will be dominated by Trump’s increasing array of unilateral disputes.

Most notably, Trump is expected to meet with Chinese President Xi Jinping on the sidelines of the G-20 summit on Saturday. Trump has warned that if talks to end the trade war fail, he will go to “plan B”: imposing billions more dollars’ worth of tariffs.

Some nations have sympathy for Trump’s pushback against China. But the unpredictable and indiscriminate nature of Trump’s global trade battle leaves many worried they could be next. Trump has also failed to rally international support on issues on which foreign nations feel their own interests go the other way, such as isolating Chinese telecom giant Huawei.

On Iran, meanwhile, Trump’s tactics are at odds with virtually every other member of the G-20 bloc, with the exception of Saudi Arabia. While Iranian officials will not be present at the meeting, the issue will almost certainly come up — especially because many attendees are importers of Iranian oil. Abe tried to act as a mediator amid the U.S.-Iranian tensions and learned the hard way that getting between Trump and an adversary can be a mistake.

In the background of all this lurks Trump’s stalled negotiations with North Korea. Abe has urged a harder line against Kim Jong Un’s regime, but Trump will fly to Seoul after the summit, a visit many hope will kick-start talks with the North Korean leader.

Trump is also expected to hold another meeting with Russian President Vladimir Putin; if their previous meetings are anything to go by, this one will be mysterious and inconclusive.

Some analysts seem to believe that Trump might be able to sway his naysayers in Osaka. Christian Whiton, a former State Department adviser in the Trump administration, wrote in the National Interest that Trump could make history at the G-20 summit with “successful trade negotiations and improved relationships.”

But that is a minority viewpoint. Generally, the prevailing attitude is that if Trump unites anyone, it will be those against him.

Writing in the Atlantic, Peter Nicholas argued that Trump’s bluster on Iran but lack of follow-up after an American drone was downed is a bad omen for the problems he may face from Xi or Putin. Trump arrives at the summit in Osaka “at a moment when his credibility has been shaken by a failure to make good on his threats and stick to his promises,” Nicholas writes.

America’s ability to dominate the summit will not just be a reflection of Trump’s personality, but also the continuing weight of U.S. interests at a supposedly global summit. The G-20, and the smaller Group of Seven that predates it, seem like relics of a time when multilateral approaches to global problems were a real possibility.

Some world leaders, such as Mexico’s Andrés Manuel López Obrador, have elected to skip the summit to focus on domestic issues. Others appear dismayed that Trump has managed to dominate the debate so much already. The U.S.-China clash shouldn’t be allowed to take “a multilateral body hostage,” an official in French President Emmanuel Macron’s Elysee office complained to Reuters.

“Our peers are trying to lead on issues where we used to, and Trump should just sit this one out if he’s still unwilling to participate in serious discussion of climate change and trade,” CNN analyst Samantha Vinograd writes.

For Abe, the best hope may be to focus on the agenda and hope for the best. Even though the Japanese prime minister is playing host, it’s ultimately Trump’s party — and he’ll cry if he wants to.

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