Chaos is inevitable when a hegemonic power falls into decrepitude. The United States is now that hegemonic power - the sick man of the globe -and chaos is now inevitable.

After the catastrophe of the world wars, the slogan "America First" was synonymous with shame. The United States repudiated the doctrine of isolationism, having realized at incalculable cost it was a fatal fantasy.

American statesmen thereafter pursued consistent foreign policy aims: a Europe "whole, free, and at peace," made possible by United States’ hard and soft power, in particular, through its construction of NATO and support for the European Union. NATO’s critical Article V placed Europe under a security umbrella underscored by the United States’ superior military power.

Open gallery view U.S. President Donald Trump arrives to hold a news conference after participating in the NATO Summit in Brussels, Belgium July 12, 2018 Credit: \ REINHARD KRAUSE/ REUTERS

In doing so, we ended centuries of competition among European countries to dominate the Continent by force - a series of rivalries that had repeatedly reduced Europe to rubble, each iteration more sanguinary than the last. Funds for the Marshall Plan to reconstruct Europe were conditioned upon Europe’s progress toward uniting to form a single market, with the ultimate goal a United Europe in many ways similar to the United States.

We sought to expand the free world - the world of open and prosperous liberal democracies, all engaged in free trade - through the construction of specific institutions, such the United Nations and the World Bank.

This foreign policy doctrine derived from the overwhelmingly obvious lesson of World War II. The United States could not flourish without global order, and that order must rest on American power, for no other power capable of providing it met with our trust, and no power that met our trust was capable of providing it. Constructing this order was in our interest, as was sustaining it.

If this was true then, it is true now.

Anyone who claims the American-led order is obsolete must answer the question: What exactly has changed? Geography? The rise of a more benevolent hegemon?

Russia, despite the collapse of the Soviet Union, continues to pursue the same geopolitical aims.

Either oblivious to, or supportive of, Vladimir Putin’s efforts to discredit NATO and pull apart the EU, Donald Trump has repeatedly indicated he shares the Kremlin’s goals, even though the social, economic, and political disintegration of Europe would be as disastrous for the world today as it would have been then.

Despite the division of the United States into antagonistic partisan tribes who insist they have nothing in common, the retreat of the United States into solipsism and indifference to the world actually began under Barack Obama, who campaigned on the promise of a disengagement from the world and "nation-building at home." He was rewarded by the electorate’s enthusiastic affirmation. Trump’s foreign policy does not represent a repudiation of the Obama Doctrine. It is fundamentally the same philosophy.

But Trump has behaved so erratically, and has been so overtly hostile to our allies and so sycophantically enthusiastic about our adversaries, as to cement American isolationism and set the world on an irreversible course toward chaos.

Open gallery view US President Donald Trump poses with Germany's Chancellor Merkel, NATO Secretary General Stoltenberg , Britain's Prime Minister May in a group photograph at the NATO Summit in Brussels. July 11, 2018 Credit: AFP

Before Trump’s election, America's allies allowed themselves to believe that American foreign policy under Obama was a bizarre experiment, not an inexorable trend, and that the next president would seek to compensate for Obama’s failings, not accelerate them.

But Trump has proven that Obama was no accident. A very sizeable constituency of Americans, of both parties, genuinely no longer sees the need for the postwar order America created, and truly believes we maintain our alliances as an act of foolish largesse - or a dangerous provocation. There is enough public support for American retreat that no country, including Israel, can now say, with confidence, that America will be a reliable ally in three years’ time - or seven.

Last week, as feared, the president of the United States used the NATO summit to display his ineptitude in diplomacy. He casually insulted our allies while lying to the American public about the nature of the NATO alliance. He lied about everything, in fact, in full view of leaders who know he’s making up every word. He singled out Germany for particular scorn. Nicholas Burns, the former U.S. ambassador to NATO, implored Americans not to "normalize" this: "He is the first American president since Harry Truman ... to not believe that NATO is central to American national security interests."

Following this, the special counsel investigating Russian interference in the 2016 election issued an indictment of another 12 Russian intelligence officers. This has not dimmed Trump’s insistence upon meeting Vladimir Putin next week - alone, without advisors, without a stated agenda - in Helsinki.

The message is unambiguous: As of now, no NATO member, nor any other American ally, can predicate its long-term defense posture on the assumption of American stability or even rational American self-interest. The constituency of Americans who were willing to vote first for Obama and then for Trump is so big that no responsible defense establishment could bet its country’s future on the assumption that Article V remains a credible promise.

Every major NATO member will now be obliged to begin considering seriously two options: an independent accommodation with Russia, or the acquisition of an independent nuclear deterrent.

Open gallery view People attend 'Helsinki Calling' protest ahead of meeting between the U.S. President Donald Trump and Russian President Vladimir Putin in Helsinki, Finland. July 15, 2018 Credit: \ LEONHARD FOEGER/ REUTERS

In 1922, Germany and the Soviet Union signed the Treaty of Rapallo. They agreed to drop all claims against the other, normalize diplomatic relations, and "co-operate in a spirit of mutual goodwill in meeting the economic needs of both countries." Both denied publicly that they had also established extensive military cooperation. But they had.

It is too early to say whether we will see Rapallo redux, or a nuclear-armed Germany, but it is not too early to say both are now imaginable. Either outcome would represent a geostrategic disaster.

NATO wasn’t formed as a charity, nor was the EU created, as Trump believes, to "take advantage" of the United States.

A world without NATO will be one in which America competes with Russia and Germany for control over the Atlantic and has no control over the new nuclear states that will emerge.

The Sonderweg interpretation of German history holds that Germany can never truly share Europe’s destiny, for history has placed it, unlike the rest of Europe, on a "special path." The thesis that purports to explain continuities between the nineteenth century imperial Germany and the rise of Hitler. Should the European Union disintegrate, Germany may find itself on a new Sonderweg - unleashed from its postwar alliances, and unconstrained by the European Union.

Either prospect would have predictable consequences: the rest of Europe would revert to its traditional fearful posture toward Germany and resume its efforts to contain German power. Recall that it will be doing so in the wake of the economic calamity that would ensue from the EU’s collapse. We do not have to wonder, theoretically, whether this experiment might go wrong.

Open gallery view Souvenir matryoshka dolls depicting Vladimir Putin and Donald Trump on sale in Saint Petersburg, Russia. May 31, 2017 Credit: Bloomberg

The transatlantic alliance has been the heart of the postwar liberal order. But in the past decade, this alliance of free countries with a deep and shared commitment to liberal democracy has been weakened to the point that a strong gust of Trump’s hot air could hasten its collapse.

Trump alone is not responsible for this: Illiberal actors - particularly Russia, the far-right, the far-left, and a host of Islamist groupings and states - understand perfectly that a united West is the prerequisite for liberal democracy’s survival. It is, not incidentally, a prerequisite for Israel’s survival, as well. Russia, above all, has embarked upon a systematic campaign to alienate Americans from Europe and European nations from one other.

Their efforts have been dismayingly successful. We are now seeing their fruit. The president of the United States, for reasons no one quite understands, now gives every impression that he is actively trying to disunite the West and the global order that has allowed it to flourish.

Perhaps this is because he’s a senile dotard who has no idea what he’s doing. Perhaps it is because he is under Russian control. Or perhaps he genuinely wishes to see it collapse. These questions will be debated for centuries by historians.

But for our purposes, it does not matter: The catastrophic effect is the same.

Claire Berlinski is a freelance writer who lives in Paris. Her forthcoming book is The Rise of the New Caesars and the Death of Freedom. Twitter: @ClaireBerlinski