President Donald Trump landed in Quebec with a confident swagger and determination, confident in his approach on everything from steel and aluminum tariffs to the Iran nuclear agreement and trade. The only problem for Trump was that nobody else in the G-7 group of industrialized nations (with perhaps the new populist coalition government in Italy as the exception) supports Trump's views on these issues.

It’s quite easy to take a glance at the traditional “family photo” of the G-7 leaders and assume that all is cordial in the group. Pictures, however, can be highly deceiving—one doesn’t need to look too far below the surface to recognize the wide disparity of opinion between the American president and every other politician at the meeting. In fact, one doesn’t even have to look under the surface to watch the intense fight unfold over global trade, tariffs, and the rules-based international order. For instance, Trump, French president Emmanuel Macron, and Canadian prime minister Justin Trudeau aired their dirty laundry on the Twittersphere even before the G-7 began. Macron, who appeared to have had some success in schmoozing Trump in the past, is now angry at the direction transatlantic relations have taken. “The American President may not mind being isolated,” Macron tweeted, “but neither do we mind signing a 6 country agreement if need be.”

The subtext is as clear as day: “Mr. President, start acting like a friend. We are all on the same team. But you are causing a dramatic fissure in the family by pursuing a trade war that helps no one and hurts everyone. And you’re doing it while taking us for granted.”

As a general rule, the foreign-policy establishment in Washington, DC. sympathizes with this message. The establishment is terrified that Trump is ripping apart the fabric of the very global system that the United States constructed out of the ashes of World War II. To employees of the Council on Foreign Relations, the Brookings Institution, and the New York Times editorial board, Trump's ego, obsession with picking worthless fights, and his desire to win at all costs are just as crippling to the international system's health as actions by revisionist powers. For example, they would see Trump's actions and nature as on par with the global damage caused by Vladimir Putin's murdering of Russian dissidents on British soil or China's moves in the South China Sea. Publications like the Economist, Der Spiegel, and the New Yorker have devoted issue after issue, and cover story after cover story, reminding readers around the world about the virtues of the post–World War II system. They write about free and open trading regimes and the importance of collective security alliances like the North Atlantic Treaty Organization. These newspapers also expound upon the indispensability of America’s responsibility to uphold international security, enforcing the rules, and protecting the globe from the latest Putin-orchestrated shenanigans. Finally, there is a genuine worry in the Euro-Atlantic diplomatic and security community that Trump is singlehandedly tearing the transatlantic alliance apart—and even worse, that he is doing it with a smile on his face.

As the Economist put it in their June seventh cover story, “He [Trump] is wrong . . . to think that America loses by taking on the costs of global leadership and submitting itself to rules. On the contrary, rules help deter aggressors, shape countries’ behavior, safeguard American interests and create a mechanism to help solve problems from trade to climate change.” American leadership, in short, is the fuel that keeps the free world running.

Diplomats in Brussels, cabinet officials in London, think tank scholars in Washington, and a clear majority of the G-7 simply don’t understand the rationale behind President Trump’s decisions. It’s inconceivable and nonsensical to many of them how Trump can believe that slapping a 25 percent tariff on steel imports is a good idea for global commerce. They also don’t understand how unilaterally withdrawing the United States from an effective multilateral nuclear agreement that is constraining Iran’s nuclear enrichment capability is a boon to the cause of nonproliferation. Others, like United Kingdom prime minister Theresa May, are puzzled about why Trump would even bring up the idea of re-inducting Russia into the G-7 when, three months prior, two Russians living in Britain were almost poisoned to death presumably on Moscow’s orders. There is just so much about Donald Trump that traditional U.S. allies are unable to comprehend.

Part of this bewilderment by allies on how to understand Trump can be explained by psychology. In style, substance, and life experience, Trump is the polar opposite of a Bill Clinton, George W. Bush, or Barack Obama. Those three previous American presidents followed White House protocol to the letter and respected the extent to which alliances could serve as force multipliers. French presidents and British prime ministers have experienced family quarrels with the United States before. For example,  the 2003 invasion of Iraq shook the U.S.-French relationship like no other decision in the post–Cold War period. Yet, the infighting was never nasty enough for European leaders to doubt America's commitment to the world as we have known it for the last seventy-plus years. Trump is a whole different animal than the conventional politicians that UN bureaucrats, German finance ministers, and NATO officials have collaborated with in the past and indeed prefer.

However, at some point, one has to wonder what is taking the rest of the world so long to understand how Trump views matters of international trade and security. Despite Trump soon entering his nineteen month in office, foreign leaders like Trudeau, Macron and German chancellor Angela Merkel still find themselves shocked, confused and outraged whenever the White House challenges the conventional wisdom that they have taken as a fait accompli. Trump is frequently depicted in the media as an unpredictable personality with no firm belief system on any subject. But if one were to delve into his writings and take a look back at his roughly forty years of public comments (as the Brookings Institution’s Thomas Wright admirably did during the 2016 presidential campaign), one can pick up a few guiding principles. First, the United States is a dumb, easily fooled giant that gets ripped off by much smaller and less powerful nations. Second, America’s allies in Europe, Asia, and North America should start showing a little more respect, admiration, and thanks for American protection. And three, the United States no longer has the money, time, or interest in riding around the world like a white knight slaying every evil, fire-breathing dragon that rears its head. These principles have not fundamentally changed since Trump took office and are what guide his decisions.

One can agree or disagree with this worldview, and there are legitimate points to be made on both sides of the ledger. But this is how Donald Trump sees the world—as one, never-ending competition between states for power, wealth, prestige and influence. The president’s worldview may be a nightmare for many, and yet it shouldn’t be a mystery. The only mystery is why leaders like Macron, Merkel, Antonio Guterres, and Jean Claude Juncker are still taken aback by their American colleague.

Daniel R. DePetris is an analyst at Wikistrat, Inc., a geostrategic consulting firm, and a freelance researcher. He has also written for CNN.com, Small Wars Journal and The Diplomat.

Image: Republican presidential nominee Donald Trump gestures to supporters as he departs a campaign rally in Clive, Iowa, U.S., September 13, 2016. REUTERS/Mike Segar