The phalanx of European leaders, ministers, and dignitaries, attending the inauguration of Iranian President Hassan Rouhani last weekend was a stunning snub to Washington. It was also a clear signal the US is losing its thrall over Europe.

Think about it. According to US President Donald Trump and the American Congress, Iran is the world’s biggest state sponsor of terrorism. And yet here we saw European leaders respectfully attending the swearing-in of the country’s re-elected president. A rather big contradiction, don’t you think?

Federica Mogherini, the EU’s highest ranking diplomat, was accompanied at the Iranian presidential ceremony by French Foreign Minister Jean-Yves Le Drian and Germany’s Minister of State Michael Roth. Also in attendance were ministers and dignitaries from Austria, Britain, Denmark, Italy, and the Netherlands, as well as many other non-European countries.

So, what’s all this American talk about Iran being a rogue state, a scourge of global terrorism? The presence of European officials – and the absence of American ones – during the inauguration of President Rouhani was a spectacular demonstration of dissonance and repudiation of American policy.

Only a few weeks ago, in May, while President Trump was on his first overseas official visit in Saudi Arabia, he called on all nations of the world to boycott Iran. Trump told assembled Arab leaders then: “All nations of conscience must work together to isolate Iran,” accusing the Islamic Republic of threatening Middle East security.

Evidently, European countries have ignored Trump and his demeaning caricature of Iran.

Indeed, ever since the July 2015 signing of the international nuclear accord between Iran and six other world powers (the US, Russia, China, Britain, France, and Germany), European governments and businesses have been hot on the trail to Tehran to ink new joint ventures and investment deals.

The nuclear accord – known as the Joint Comprehensive Plan of Action (JCPOA) – has lifted international sanctions on Iran in return for it adhering to restrictions on its nuclear program to bar weaponization. Six reviews carried out by the UN watchdog, the International Atomic Energy Agency, have verified Iran is in full compliance with its side of the JCPOA bargain.

The Europeans seem more than happy about that. Federica Mogherini, the EU foreign affairs chief, is a formidable advocate of the nuclear deal, proclaiming it a success and a source of regional stability. Iran’s Foreign Minister Mohammed Javad Zarif was warmly welcomed in Brussels in June when he reported via Twitter: “Excellent meeting with leaders in Berlin, Rome and Paris. Despite reckless US hostility, EU committed to JCPOA and constructive engagement.”

European investors have duly piled in to snatch part of the Iranian market of some 80 million people and the world’s second and fourth largest source of natural gas and oil, respectively.

This week, two days after Rouhani’s inauguration, French automaker Renault signed the “biggest-ever” car deal in Iran, worth €660 million, where it will manufacture 150,000 vehicles a year in partnership with two Iranian firms.

Last year, French company PSA, the maker of Peugeot and Citroen, announced a similar investment in Iran, worth €400 million.

The champion breakthrough for European-Iranian investment came last month when France’s Total signed up to a nearly €5 billion 20-year project with Iranian and Chinese firms to develop Iran’s South Pars gas field in the Persian Gulf, reckoned to be the world’s biggest reserve.

Both Germany and France have seen exports to Iran soar since the implementation of the nuclear accord. Germany’s by some 26 percent and France’s by nearly 50 percent, according to trade figures.

Eric Schweitzer of the German Chamber of Commerce estimates his country’s bilateral trade with Iran will double within the next two years. Being the kingpin economy of Europe that means a burgeoning relationship between the wider EU and Iran.

It was notable the EU’s Mogherini said last month the JCPOA “does not belong to any one country,” when she met with Russian Foreign Minister Sergey Lavrov in Brussels. This was a veiled notice to the US that the Europeans intend to implement the nuclear accord with or without the Americans. Russia and China are, of course, onboard with the agreement, both having signed significant energy deals with Iran over the past year.

By contrast, Washington has signaled that it may rip up the JCPOA. President Trump has so far reluctantly gone along with the accord, which was negotiated under the previous Obama administration. Nevertheless, Trump has reportedly sidelined his Secretary of State Rex Tillerson, an ex-oil CEO, and is pushing to rescind American compliance.

Such a reversal would have legal implications since the JCPOA is an internationally binding treaty confirmed by the United Nations. What Trump’s White House will seek to do is either ramp up accusations that Iran is in breach of it by testing ballistic missiles or try to antagonize Iran into rejecting the JCPOA by slapping on more bilateral sanctions against the Islamic Republic. Last week, Trump signed into law new sanctions targeting Iran, as well as Russia and North Korea.

These “secondary sanctions” – which nominally are unrelated to the nuclear deal – will also potentially target European banks and industries over investments in Iran.

Thus, while European businesses and governments are legally entitled to partner with Iran due to the JCPOA terms, Washington is seeking to impose obstacles on the grounds of its bilateral sanctions based on dubious allegations of Iranian links to terrorism or illicit development of ballistic missiles.

This echoes the same repercussions for Europe about new American sanctions imposed on Russia over its natural gas delivery projects to the continent. British, French, German and Austrian energy firms are threatened with American penalties because of their partnership with Russia’s Gazprom in the construction of the Nord Stream-2 pipeline.

Europe’s response to those American sanctions has been furious, condemning Washington’s policy as blatant interference in EU energy security.

Iran is another flagrant case in point, where European economic and political interests are being dictated to by Washington.

However, increasingly it seems, the Europeans are realizing through bitter experience that Washington is not acting out of some benevolent “transatlantic unity” but rather for its own base, selfish strategic interests.

Whether it’s the Paris climate agreement, the Iranian nuclear accord, or sanctions on Russian energy supplies, the Europeans are on a journey of political discovery, in which they will fully realize their so-called strategic partnership with the US is, in fact, a huge liability.

As Deutsche Welle reported earlier this month: “Europe and USA on a collision course over Iran nuclear deal.”

Europe needs to extricate itself from the double think of following American sanctions against Iran and Russia, while also being penalized by Washington at almost every turn.

As the Americans famously say: “There’s no such thing as allies, only interests.” It’s surely time for Europe to put its own interests first and forget about fictitious allies.

Not only is the American “ally” fictitious; it is also destructive and rather dangerous to be around.