Former London mayor Boris Johnson leaves his Islington home on July 1 in London. (Jack Taylor/Getty Images)

LONDON — When the news broke Wednesday night that former London mayor and pro-Brexit campaigner Boris Johnson would become Britain's next foreign secretary, his future counterparts abroad and political analysts at home were equally taken by surprise.

Just two weeks ago, Theresa May herself had joined the chorus of Johnson critics: "Boris negotiated in Europe," she said back when the Conservatives were still elbowing one another to be the party's premier. "I seem to remember last time he did a deal with the Germans, he came back with three nearly new water cannon." It was a reference to how May, during her time as home secretary, prohibited Johnson from deploying his newly bought German water cannons on the streets of London over safety fears, publicly shaming him.

Her words two weeks ago were also supposed to send a clear message: This man is not ready for real-world diplomacy. But minutes after becoming prime minister on Wednesday, May made Johnson her top diplomat.

Abroad, Johnson has repeatedly provoked backlashes in recent years, like when he called President Obama "part-Kenyan" or when he described Turkish President Recep Tayyip Erdogan as having sexual congress with a goat in a poem published only two months ago.

Both Donald Trump and Hillary Clinton might also want to have a few words with Johnson: The new British foreign secretary previously compared Clinton to "a sadistic nurse in a mental hospital." Of Trump, Johnson said: "The only reason I wouldn't visit some parts of New York is the real risk of meeting Donald Trump."

And in 2006, Johnson suggested that the West should not panic if Iran gets a nuclear bomb.

Those comments were frequently condemned or ridiculed, but their backlash targeted Johnson himself, not the country whose highest office he sought until only weeks ago. Now, Johnson is Britain's highest-ranking international representative, and his words will carry great weight. Johnson himself acknowledged this in an interview with ITV Television on Wednesday evening, suggesting that he would have to apologize to multiple nations and world leaders. "The United States of America will be at the front of the queue," he said.

So, why did May think it was a good idea to give Johnson the job in the first place?

Some of the potential advantages of giving Johnson a top role in her new cabinet are hard to refute. The former London mayor played a crucial role in the Brexit campaign, whereas May showed loyalty with David Cameron and backed the prime minister's "remain" campaign.

Although she has been credited by the "leave" camp for vowing to make Brexit reality following the referendum, there are still many skeptics who wish Johnson, Michael Gove or Andrea Leadsom had won the Conservative Party leadership contest instead. Including the still-quite-popular Johnson in the government could mute their criticism and reduce pressure on May.

In his new position as foreign secretary, Boris Johnson is also less likely to become a direct political threat to Theresa May in the foreseeable future. His criticism of her government could have been particularly strong. "Johnson, bored and sidelined, would have had plenty of time to think up jokes about her and her government; now he’ll be on a plane to Timbuktu instead," my colleague Anne Applebaum commented.

Some argue that Johnson's undiplomatic character might be exactly what could be needed to reposition Britain outside of the European Union. "I think this is actually a bold appointment," Sir Christopher Meyer, a former British ambassador to the United States, was quoted as saying by Sky News. "We need now to send a shot of adrenaline through our diplomatic system so we raise our game all round the world. And I think Boris Johnson is capable of doing precisely that."


Boris Johnson stands with his "Bear of London" Paddington Bear statue during the launch of The Paddington Trail at London's City Hall on Nov. 3, 2014. (Ian Gavan/Getty Images)

Although much of the British media's reaction to Johnson's appointment has consisted of ridicule, there has been signs of support. "He has become a globally recognisable figurehead and if anyone can persuade our international partners that a Brexit vote was one of a self-confident nation keen to secure existing relationships and strike new alliances, he can," wrote Evening Standard columnist Pippa Crerar.

But others believe that Johnson was appointed for far different reasons: Was Theresa May mainly searching for someone she could blame, should negotiations with the E.U. stall?

The power of British foreign secretaries has diminished in recent years. There will be a separate Brexit minister, David Davis, as well as a new department which deals with international trade. Yet it might be Johnson who will be publicly held accountable.

Shortly before the referendum in June, Johnson said he would make a public TV apology should Brexit lead the country into a recession. “I don’t think London has anything to fear from coming out of the E.U., and neither does Britain," said Johnson. Recent economic forecasts, however, have painted a much gloomier picture of the United Kingdom's future. As unemployment is expected to rise the country might now indeed face a recession next year.

It was also Johnson who made some of the Brexit promises that might never become reality. He frequently claimed that the U.K. was sending 350 million pounds to Brussels every week — although the actual contribution is far lower. Johnson said that British funding to the E.U. would be used for the country's health-care system after Brexit. But other leading "leave" campaigners have since expressed doubts that this will ever happen.

Johnson was strongly criticized by fellow Brexit campaigners for a column he wrote in the Telegraph after the referendum. "EU citizens living in this country will have their rights fully protected, and the same goes for British citizens living in the EU," Johnson wrote in it, striking a sensitive nerve among many patriotic voters. Many had voted for Brexit to stop the influx of E.U. migrants into the country.

Johnson's quick reassurance also contradicts Theresa May who recently said that the future of E.U. nations in the U.K. was still uncertain. The decision could affect more than 3 million non-British E.U. citizens in the U.K. and more than 4 million British citizens living outside of the country.

If Britain wants to remain in the E.U. single market (and economists say not remaining could have worrying repercussions), it will likely need to continue to allow E.U. migrants to enter the country.

Someone will have to explain this to the Brexit voters, eventually.

Jennifer Hassan contributed to this report. 

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