Jean-Claude Juncker’s trade truce with Donald Trump is really bad news for Theresa May and her Chequers Brexit plan. But it could be good news, long-term, for the British economy.

The EU’s sly old Luxembourgish fox went to the White House Wednesday and delivered what’s known in Brussels lexicon as “European added value.” And the Commission president delivered it big-time, convincing the combustible, finger-wagging American president to forestall tariffs on EU cars, which Trump has repeatedly threatened and which represented Germany’s worst possible fears in terms of escalation of a trade war.

What’s bad for May in the Brexit context is that Juncker pulled off his unexpected deal by sticking hard and fast to EU principles and priorities. Juncker ultimately offered Trump only things — such as buying more American soybeans or building liquefied natural gas platforms — that the EU was willing to do anyway, or was already doing. In the case of working to eliminate tariffs on industrial goods, it was an offer previously made to the Obama administration as part of negotiations on the now-defunct Transatlantic Trade and Investment Partnership (TTIP).

In other words, Juncker not only did not cross or redraw any EU red lines, he didn’t even tiptoe up close to one. Instead, he took out his red magic marker, and went over all the lines a few extra times to brighten and clarify: The EU is the world champion of rules-based international free trade, it opposes tariffs and wants to strengthen the World Trade Organization.

And it doesn’t back down.

For political reasons, Trump could have stood his ground.

May and her new Brexit secretary, Dominic Raab, should take notice. Juncker's performance in Washington shows that even when confronted with a global bully like Trump, the EU will stick to its guns.

There's an even more appealing takeaway that Juncker and chief Brexit negotiator Michel Barnier hope the U.K. will take heed of: Pick yourself a victory when one is handed to you on a platter. Just as everything Juncker offered Trump was in the indisputable best economic interest of the U.S., everything Barnier is offering the U.K. at the negotiating table is in Britain’s own best economic self-interest — according to the U.K. government’s own analyses.

For political reasons, Trump could have stood his ground. He could have fretted about how everyone would say that the deal was much better for the EU than for the U.S. But defying all expectations based on previous erratic behavior, he took a result that could be spun as a win.

There was a poetic parallel in U.K. International Trade Secretary Liam Fox being in Washington on the same day as Juncker and his entourage, working to gin up interest and support for a post-Brexit trade deal — a visit that got little notice. Senators Chris Coons of Delaware and Rob Portman of Ohio, who chair the Senate U.K. Trade Caucus, met Fox and then issued a statement, noting their “commitment to pursuing a mutually-beneficial bilateral trade agreement between our two nations after the Brexit process is complete.”

Where Trump expressed excitement about his deal, citing the robust size and scope of the EU market, the senators stressed home-state interests. “We remain committed to strengthening trade ties between our two nations and building support for an eventual agreement that will boost American exports and support jobs in Delaware, Ohio and across the country,” they said.

The difference in global political heft was there for all to see.

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