The president of the United States has put at risk that historical heritage called the West, which hinges on transatlantic relations.

Donald Trump did not wait until Saturday’s deadline: Last night, after giving notice to the entire world, he announced the withdrawal of the U.S. from the Iran nuclear deal of 2015. The sanctions, which had been withdrawn in exchange for the restrictive clauses imposed on Iran by the deal reached in Vienna, will be progressively reintroduced by July. Moreover, the head of the White House has authorized additional sanctions against Tehran as a strike against its experiments on ballistic missiles, its military expansion in the Middle East and the lack of guarantees against nuclear projects resuming after 2025.

Therefore, Europe’s diplomatic pressure was in vain. Boris Johnson’s arguments fell on deaf ears, as he brilliantly summarized the fears of America’s European allies over the last days, especially now that London is preparing to divorce the European Union: The 2015 agreement does have its downsides, but it was and still is needed to restrain possible nuclear ambitions in Iran. The International Atomic Energy Agency’s checks are the strictest ever carried out and have confirmed nine times that Tehran is respecting the terms of the agreement. Should the deal be dissolved after the United States’ decision, Iran may go as far as to resume enriching uranium unchecked and withdraw from the non-proliferation deal. The issues raised by Washington can be tackled, but it is wrong to destroy what was achieved in the absence of valid alternatives.

Trump and his new advisers, Mike Pompeo and John Bolton, listened without hearing, as the president’s true priority was to undo Obama’s pledge and show his voters that his campaign promises are being kept. While paying heed to his domestic front and being backed by Benjamin Netanyahu, the head of the White House has, however, caused a rift that will be difficult to mend with traditional European allies. They will attempt to salvage the agreement by continuing to hold up their end and asking Iran to do the same, but they will have to deal with two important unknown quantities: the political future of Hassan Rouhani’s reformists in Iran — the “hawks” will get their revenge — and the nature of American sanctions. According to Trump’s announcement, Washington will inflict on its allies so-called secondary sanctions, meant to penalize any entity that conducts business with Iran. Businesses which had resumed their activities over there (some of which are Italian) would then be induced to flee, as they also do not want to lose access to the U.S. market. Iran would retaliate once again, meaning that the possibility of a war, which was raised by Emmanuel Macron over these last few days, becomes increasingly likely. The French president was indeed warned in advance by Trump yesterday, but he had to reckon with the extent of his false hopes and ambitions anyway.

Russia and China immediately disapproved of Trump’s choice, too. That said, the real wound created by the U.S does not involve the already difficult relations with Moscow and Beijing, and not even the admittedly grave consequences that may occur in Iran. The wound has been dealt to the historical heritage called the West, which hinges on transatlantic relations. It has been almost 30 years since the Berlin Wall fell. Considering a new international system to replace the one of opposing blocks makes sense. Nevertheless, what is going to happen to the West along the way? The real struggle seems to occur over the geopolitical consequences of “America First,” the matter of American tariffs that weighs on Europe as well as on China, transatlantic ideas and interests becoming increasingly divergent as Trump has split America in two and Europe has fallen prey to rampant and destabilizing nationalisms.

Trump is not always wrong. He has a point when he asks European countries to contribute more to NATO’s common defense budget. However, his suspicion and hostility toward the efforts to create a European defense are mistaken. In this area, as well as in others, strategic plans become muddled with the mood of the masses, empowered in our democracies by elections. Part of the reason why Trump ruined the Iran deal is that the president is already in campaign mode for 2020, as “Russiagate” and other unsavory matters close in on him.

Regarding Europe, we cannot forget than Angela Merkel has been weakened, that Macron has received the harshest blow from Trump and is now struggling to retain social approval, and that Theresa May deserves credit for keeping London close to its European allies, but her future is uncertain. The rejection of the Iran deal was also caused by the sum of these weaknesses. Let us also not forget that Italy is still embroiled in its own political turmoil and is unable to defend its own interests. As both Brussels and Washington know, its international isolation risks becoming permanent. After yesterday’s break, conventional Atlantic solidarity will no longer cut it. The same goes for bombings like the one in Syria and even the common satisfaction with which Trump and Kim Jong Un’s meeting will certainly be viewed. Starting today, the West acknowledges its crisis. Unless it changes its path, one day it will realize that it has handed a wonderful present over to Vladimir Vladimirovich Putin.