Despite the calls of the overwhelming majority of the international community for the United States to stay in the Iran nuclear deal, US President Donald Trump announced on Tuesday that he will withdraw the US from the pact and reimpose sanctions against Teheran. His decision is not only a blow to the agreement itself but also renounces the multilateral efforts that secured the compact.

In July 2015, after two years of tough negotiations, Iran and six world powers – Britain, China, France, Germany, Russia and the US, plus the European Union – reached a deal, in which Iran would freeze its nuclear weapons program in exchange for the US and the EU lifting sanctions.

Since the deal went into effect on October 18, 2015, the International Atomic Energy Agency, the United Nation’s nuclear watchdog, has confirmed ten times that Iran has fully complied with the obligations set out in the deal.

Trump withdrawing the US from the deal puts the multilateral deal in jeopardy, which in the worst-case scenario, as some have already warned, could lead to war with Iran.

However, Germany, France and the United Kingdom have all staunchly defended the deal, saying they are committed to it. That they are not willing to follow the US' lead this time offers hopes that the deal may survive without the US.

But whatever happens to the deal itself, Trump's move has immediately thrown US-Iran relations into confrontation again. Something that will not help to calm the turmoil in the Middle East. Especially, as the move seems intended to accelerate the force regime change in Teheran that Washington and its Middle East allies seem to be seeking.

It also sends the wrong message to the Democratic People's Republic of Korea at a crucial moment.

This is not the first time that Trump has torn up a multilateral deal. From the Paris climate change pact to the Trans-Pacific Partnership trade agreement, Trump’s “America First” doctrine has proved to mean the US will not be beholden to its promises.

While it is natural that the US leader should want to put his country's interests first, those interests do not exist in a vacuum. In today's interconnected world, the butterfly wings of even minor decisions can result in significant and unforeseen consequences elsewhere. And those in their turn also have their own butterfly effects.

Trump wants to improve the US' fortunes, which is all very well. But he is not a fortuneteller. Nor is anyone else in his administration. Not even whatever algorithms they might be using can predict every eventuality.

The deal was working; that much is known. It would have been much better to leave it alone.