French President Emmanuel Macron, German Chancellor Angela Merkel and U.S. President Trump speak at the G20 meeting in Hamburg, Germany on July 7, 2017.John MacDougall / Reuters

Before the United States announced Thursday that it would impose steel and aluminum tariffs on the European Union, the Europeans had already resigned themselves to their fate. After months of lobbying Washington for a permanent waiver from the tariffs, the EU this week dropped expectations that it would receive any sort of exemption. Instead, it cautioned its members to “prepare for the worst.” The levies are expected to go into effect on Friday.

In many ways, the Europeans probably saw this coming a while ago. After all, President Trump’s decision to impose a 25-percent steel tariff and 10-percent aluminum tariff on key U.S. allies, which he said is necessary for the country’s national security, marks just one in a series of recent blows to the transatlantic alliance. It also caps a year defined by policy divergence, during which two allies accustomed to standing shoulder to shoulder have found themselves increasingly on opposing sides.

The first of these divergences came almost exactly a year ago, when Trump announced that the U.S. would withdraw from the Paris climate accord, the first international treaty to combat climate change. The move was met with criticism around the world, though no one voiced their disappointment as strongly as French President Emmanuel Macron. After reaffirming that France and its partners would continue to uphold the agreement without the U.S., the French leader reminded Americans that “we all share the same responsibility” to, borrowing from Trump’s campaign slogan, “make our planet great again.”

The second major division came months later when Trump announced that the U.S. would recognize Jerusalem as the capital of Israel. The controversial move reversed decades of U.S. foreign policy, which had up until that point deemed the city disputed territory between Israelis and Palestinians. But it also put the U.S. squarely at odds with its European partners, who rebuked the move and widely declined invitations to attend the embassy’s opening earlier this month (of the bloc’s 28 member states, just four sent their ambassadors).  

Then there was Iran. In what has arguably been the greatest break in the the transatlantic alliance under the Trump administration, Washington announced earlier this month that the U.S. would withdraw from the Iran nuclear deal. Just as it had done ahead of Trump’s decision on the Paris accord and the steel and aluminum tariffs, the EU went to great lengths to try and convince Trump not to abandon the deal—even going so far as to dispatch France’s Macron, German Chancellor Angela Merkel, and British Foreign Secretary Boris Johnson to Washington to make their case. Though unsuccessful, the EU reaffirmed it would fight to preserve the deal, even if it means doing so without Washington. It adopted a similar posture with regard to the Paris accord and Jerusalem.  

While the U.S. and EU’s divisions over climate, foreign policy, and trade are not the sum total of their disagreements (Trump has also feuded with various EU countries over their response to terrorism and their NATO defense-spending contributions), it does mark an extraordinary trend. Despite their deep historical ties and their continued close cooperation on issues such as counterterrorism and security, the U.S. and the EU now find themselves on divergent paths—with one side careening towards “America First,” while the other continues toward “multilateralism.”  

“To some extent the frictions and tensions in the transatlantic relationship resemble the kind of things that were voiced under the presidency of George W. Bush,” Marianne Schneider-Petsinger, a U.S. geoeconomics fellow at the London-based Chatham House, told me. “But it’s a different tone. Under Bush, the concern for the transatlantic relationship was an overreach of American power. Now, I see it more as a question about the future of U.S. engagement in the world and how it values alliances, particularly with its European partners.”

In response to this latest rift, the EU has said it would take the issue to the World Trade Organization and impose its own retaliatory tariffs, which target American goods from key U.S. congressional districts such as bourbon whiskey and Harley Davidson motorcycles. “Throughout these talks, the U.S. has sought to use the threat of trade restrictions as leverage to obtain concessions from the EU,” the bloc’s trade commissioner Cecilia Malmström said in a statement Thursday. “This is not the way we do business, and certainly not between longstanding partners, friends, and allies.”

The dispute is unlikely to end there, either. French Finance Minister Bruno Le Maire warned Thursday that the imposition of steel and aluminum tariffs could lead the U.S. into “a trade war with their closest partners,” echoing a similar threat made by French President Emmanuel Macron earlier this week. “Trade wars quickly become war—full stop,” Macron told the Organization for Economic Cooperation and Development forum Wednesday in Paris.

But the U.S. seems more than willing to call their European partners’ bluff. Also speaking at the OECD in Paris this week, U.S. Commerce Secretary Wilbur Ross said the U.S. isn’t after a trade war, adding, “If there is an escalation it will be because the EU would have decided to retaliate.”

Trade ties could get even worse. Trump is reportedly considering imposing a ban on German luxury cars from U.S. markets, which would likely prompt further EU retaliation. “This I think is the next iteration of the tariff and trade conflict between the United States and the European Union,” Schneider-Petsinger said. “Exports of cars and automobiles to the United States are quite significant. … I don’t see this rift being healed anytime soon.”

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