Media playback is unsupported on your device Media caption Do Americans recognise UK's new prime minister?

What's an American to make of Boris Johnson?

Not the person-on-the-street American, who may look at a photograph of the new British Conservative leader and think they're being asked to identify an aging 1970s glam rocker.

I'm talking about the US media analysts and commentators who get paid to think about politics and, occasionally, cast their eyes across the oceans to see what the rest of the world is up to.

At this point in US history, it's hard for Americans to view any major political event outside the context of the rise and rule of Donald Trump - the crashing cacophony that drowns out all other thought.

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Such is the case with the Mr Johnson. The comparisons between the two Anglophone leaders have come fast and furious - some facile and others more nuanced. Even Mr Trump himself got in on the game, in a speech in Washington on Tuesday afternoon.

"He's tough and he's smart," Mr Trump said of Mr Johnson. "They call him 'Britain Trump', and it's people saying that's a good thing. They like me over there. That's what they wanted. That's what they need."

There are plenty of other opinions, of course - that Mr Johnson is either the second coming of Donald Trump in a good way or in a bad way; a British original or a knock-off nationalist.

"The front-runner to become Britain's next prime minister is a portly white man with unkempt blond hair, an adoring base of supporters, disdain for Europe, a dodgy private life and a loose relationship with truth and principle," the New York Times editorial board wrote last month. "There are also differences between Boris Johnson and Donald Trump, but the similarities have been much noted in some European circles, with no small misgivings."

The hair is where the comparisons always start - although the Associated Press's Gregory Katz and Natasha Livingstone note that while both pay careful attention to their trademark coifs, they do so in differing ways.

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"President Donald Trump's hair is very carefully styled before he appears in public, while Johnson's precisely the opposite," they write (in fact, Johnson is known to ruffle his hair before he goes on camera). "From the start of his political career Johnson has sported what could only be called the 'slept-on' look, declining to style his locks in any way so they have a natural, spontaneous, even unpredictable quality."

Beyond appearances, American observers note that both Mr Trump and Mr Johnson were born in New York City, and both have elite college pedigrees - the former at the Ivy League University of Pennsylvania and the latter at Oxford. The more discerning will note that Mr Johnson qualified through an academic scholarship, while Mr Trump's admission reportedly required some familial arm-twisting.

Mr Johnson also occasionally betrays his ivory tower pedigree with allusions to classical history or the arts, while Mr Trump… does not.

Both men also have taken unusual paths to power - the American through his real estate and reality television celebrity, and the Brit by being a sharp-tongued journalist.

"Johnson's rise is akin to Trump's: People in the political class don't like, or even trust, him," writes Kyle Smith of the conservative National Review. "Yet he found a path around them."

Media playback is unsupported on your device Media caption BBC political correspondent Chris Mason's guide to the political life of Boris Johnson

That path includes riding a wave of populist sentiment to the highest pinnacles of power in their countries.

"Like President Trump, Johnson is a larger-than-life populist who has made controlling immigration and restoring his nation's standing in the world key issues in recent years," writes National Public Radio's Frank Langfitt. "Like Trump, Johnson has also emphasized his unease with the changing face of his homeland, using language that plays well with much of his white base but angers minorities and urban liberals."

Despite distaste from the respective political establishments and vociferous objections from the left, both men prevailed in part through the outsized nature of their personalities. They both display an unfailing belief in the strength of their will to overcome obstacles that others have found insurmountable.

"I have joined the political arena so that the powerful can no longer beat up on people that cannot defend themselves," Mr Trump said in his 2016 speech accepting the Republican Party's presidential nomination. "Nobody knows the system better than me, which is why I alone can fix it."

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On Tuesday morning, Mr Johnson pledged to energise the country, which he compared to a sleeping giant.

"We are going to take advantage of all the opportunities that it will bring in a new spirit of can-do," he said. "And we are once again going to believe in ourselves and what we can achieve."

The Atlantic's Tom McTague writes that Mr Johnson's view of the world is "a romantic, egocentric belief in his personal power to do great things, to solve great puzzles, through the force of his personality".

Read more on the Johnson story

Mr Trump bills himself as an expert negotiator, the master of the "art of the deal" - whether it's resolving longstanding disputes with North Korea, reopening trade deals with allies, brokering peace in the Middle East or offering to be the (apparently unwanted) arbiter of the Kashmir dispute between India and Pakistan.

Francis Menton, who writes the Manhattan Contrarian blog, says the president's skill at negotiation - while the ultimate verdict is still out - is in his willingness to walk away from what he views as a bad deal. That's an attribute he suspects Mr Johnson shares.

"There is zero chance that a successful Brexit deal can be negotiated without at least some degree of brinksmanship," he says, adding that Mr Johnson's expressed willingness to accept a "no deal" Brexit demonstrates a "breath of basic competence".

As the name of Menton's blog indicates, that's largely a contrarian view in the US right now. On Tuesday morning, the New York Times editorialised that Mr Johnson's career "displays far more bluster than achievement, and a consistent disdain for hard work, probity or the truth".

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Ishaan Tharoor, in The Washington Post, writes that the new Conservative leader's "incessant appeals to the bravura and derring-do of Britain's past" is entertaining but absurd, and "won't translate easily into meaningful politics".

Many of these comparisons gloss over some of the very real policy differences between Mr Trump and his British counterpart that could outweigh their stylistic similarities and shared views on trade and immigration. Mr Johnson supports the Paris Climate Accord and the Iran nuclear deal and vociferously defends his nation's government-run healthcare system, for instance - all anathema to the US president.

Image copyright BRENDAN SMIALOWSKI/AFP/Getty Images Image caption Boris Johnson (left) and Donald Trump greet before a UN meeting in 2017

That could be why some on the American right also have their doubts about Mr Johnson.

"Boris Johnson is a fascinating and entertaining character, which is not the same as being a serious, prepared leader," tweets Dan McLaughlin, a contributing columnist with the National Review.

"He's kind of a cross between [former Speaker of the House of Representatives] Newt Gingrich and Trump, but with a distinct Fleet Street flavour and little in common with US conservatives philosophically. You'd be a fool to rule out the possibility that Boris Johnson will be a successful prime minister, though the odds are against it."

Of course, the odds were pretty slim that Donald Trump and Boris Johnson would be where they are today. Americans these days don't put a lot of faith in political probabilities.

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