EU leaders had planned to spend a summit dinner talking about an aggressive, potentially hostile, rival with aspirations of global economic and military power.

The surprise was it ended up being about Britain and not China.

This summit was not supposed to focus on Brexit at all, but rather the EU's future in a tumultuous world. As it turned out the two issues are very much intertwined.

Thursday's dinner ended up being all about Brexit, rather than Beijing as planned. But many of the concerns about competition from China, expressed by EU leaders when the postponed session finally took place Friday, echoed their worries about future competition with a newly sovereign U.K. It is these fears that have framed the bloc's negotiating positions on Brexit.

Late Thursday night, Council President Donald Tusk steered leaders to a decision to postpone the Brexit deadline that achieved his own top goal — to keep open the possibility of a longer-term delay that just might lead to Britain staying in the EU.

Tusk said that the thought of the U.K. as a rival is too awful for him to contemplate.

Tusk's persistence in harboring such hopes stems not so much from his personal affection for Britain — formed as a young Beatles fan in communist Poland — even though that appreciation is genuine. "I am more pro-British than you, I think," Tusk joked with a reporter from the U.K. Friday.

Rather, aides and associates said, it is based on his conviction that the post-Brexit relationship will not be a happy one of shared values and win-win economic ties.

Instead, he expects a competitive, even tense, rivalry in which the EU continues to serve as a punching bag for London and becomes a scapegoat for the inevitable problems, financial and otherwise, that will follow Britain's departure.

"They will blame the EU for their misfortunes," a senior official said, speaking anonymously to discuss Tusk's private thinking. "There is no bright future after Brexit."

Tusk's apprehensions reflect a warning by former U.K. Prime Minister Tony Blair, who told POLITICO last year that the U.K. after Brexit could well end up “a competitor to Europe, not an ally" in a situation that could be "very ugly."

Tusk said at the summit's closing news conference that the thought of the U.K. as a rival is too awful for him to contemplate.

"I am mentally not able to treat today equally the U.K. and China," he said. "For me the U.K. is still a member of our family, not a rival."

Fret on two fronts

But just as the EU frets about future relations with Britain, it is also grappling with a mix of apprehension — and grudging admiration — regarding China and other developing powerhouses.

European Union leaders worry about safeguarding intellectual property and demographic trends that clearly show Europe aging, shrinking and controlling a smaller and smaller share of the world economy. They also fret about disinformation, hacking and cyberterrorism being used to target developed democracies.

"In a more unstable world, shaken by new global, technological and environmental realities, there is no doubt that only together can we set our own course and defend the strategic interests of the Union," Tusk wrote to leaders in his invitation letter to the summit. "This is true whether we are talking about strengthening our economic base, combating unfair practices or tackling climate change. We will therefore discuss how to use all the levers at our disposal to safeguard the interests of our citizens and companies. China is a key global player in all these issues."

Is it tougher investment screening that commands Beijing's respect? Or warships of the Royal Navy patrolling in the South China Sea?

Unease in this age of worldwide geopolitical tumult certainly seemed to weigh on German Chancellor Angela Merkel as she intervened in Thursday's emotional debate to rebuke leaders who seemed tempted to push for a no-deal outcome and eject the U.K.

Merkel, who is serving her fourth and final term and has begun a transfer of power in Germany, is facing threats of a trade war from U.S. President Donald Trump, an economy that shows signs of slowing, and surging populism across Europe. Her level of risk tolerance seems set at zero.

"Even if you don’t need the U.K., we need them,” Merkel said during the debate, according to two diplomats who described the exchange for POLITICO's Brussels Playbook. In the moment, Merkel was admonishing Tusk for allowing the debate to dwell too long on the possibility of forcing the U.K. out without a deal. But her remark was viewed by observers as a message to French President Emmanuel Macron and others pushing a harder line.

As it tries to chart its way in the world, the EU faces a fundamental question: Is the world's foremost champion of multilateral soft power capable of ever being tough enough to assert its values and truly defend its interests?

Greece might say yes — but that was a family feud.

Russia might say no.

Britain and China will be making their own hard-headed power calculations in the years ahead.

Is it tougher investment screening that commands Beijing's respect? Or warships of the Royal Navy patrolling in the South China Sea?

Chided on China

European Commission President Jean-Claude Juncker, kicking off the discussion on China on Friday, scolded leaders for not beginning the conversation years ago. According to a diplomat in the room, Juncker noted the absence of "reciprocity in commercial relations with China" and said "the EU was wrong to hope that China would respect human rights more when economic progress increases."

In a sobering speech, Juncker said that there had been no progress on three deliverables agreed at an EU-China summit last year: opening on civil aviation; more favorable respect for geographic indications (premium EU food names); and a working group on reforming the World Trade Organization.

"The EU should be clear but more firm with China," Juncker said, according to the diplomat, and he called for stricter investment screening that would potentially curtail China's growing influence in European companies.

Although the Brexit can has been kicked, it has not travelled far down the road.

Standing with Tusk at the closing news conference, Juncker said he found it easier at the summit to discuss China than Britain. "Not because China is asking to join the European Union but because it's not leaving the European Union," he explained.

At times Juncker almost sounded like Trump in complaining about unfair trade practices. "Competition between China and the European Union is not fair," he declared.

Brexit is likely to be settled long before relations with China could ever be brought fully into balance. Although the Brexit can has been kicked, it has not travelled far down the road.

Instead of following EU leaders' advice, and requesting a new deadline before the European Parliament election starts on May 23, British Prime Minister Theresa May asked for Brexit to be postponed until June 30. And instead of offering a plan for what happens if MPs reject her deal for a third time, May simply expressed optimism that she would prevail — with no explanation of how, according to EU diplomats.

As a result, EU officials stepped in and gave her two new dates — May 22 if she wins ratification for the Brexit deal negotiated with Brussels, or April 12 to come back with a new plan if she fails.

For the moment, the EU has the upper hand and May, awaiting their discussion in a windowless room on Thursday evening, quickly accepted the offer.

Both camps described their exchanges as cordial, but there is frustration on both sides and there have been hints of nastiness in the Brexit discussions. If a no-deal outcome appears inevitable, the dynamic could rapidly shift further in that direction.

The more immediate worry for both the EU27 and the U.K. is that Brexit is distracting from bigger issues like China policy, said Amanda Sloat, a senior fellow at the Brookings Institution. Case in point: May did not attend the summit discussions on China on Saturday, saying she needed to return to London to deal with Brexit.

"I question whether the U.K. and EU will become political and economic rivals, as geography, history, financial interests, security concerns, and shared values will necessitate continued close cooperation in some form for the foreseeable future," Sloat said. "My bigger concern is the all-consuming nature of Brexit, which could prevent the U.K. especially and the EU from engaging effectively against international rivals."

Noting how the summit dinner on China became a summit dinner on Brexit, Sloat said: "Brexit already dominates debates in London, with a divided Cabinet and parliament having limited bandwidth to engage on global challenges."

She added, "Even if the U.K. parliament ratifies a Brexit deal, the two sides must then embark on equally complicated and domestically contentious negotiations about their future relationship. In some form, Brexit will afflict Europe for years and risks detracting attention from emerging threats."

Jacopo Barigazzi and Florian Eder contributed reporting.

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