Johnson was one of the most prominent pro-Brexit campaigners in 2016, and now he has inherited a political crisis that, when you break it down, still looks a long way from being resolved.

But supporters of Johnson believe that his optimism makes him the right man to dig Britain out of its Brexit ditch. And among those supporters is a certain Donald Trump.

Much has been made of the similarities between Johnson and Trump . It's a comparison that the United States President seems to like. On Tuesday night, Trump said, "They're saying Britain Trump. They call him Britain Trump and people are saying that's a good thing. They like me over there. That's what they wanted. That's what they need."

Overlooking the fact that Johnson was in fact elected by Conservative Party members ( 0.2% of the population ) rather than the country at large --- and that Trump is not in fact widely liked in the UK -- it's not a comparison that Johnson will be pleased about for a number of reasons.

First, it doesn't really stand up. There are plenty of reasons to criticize Johnson. He has said incredibly controversial things in newspaper columns and on public platforms over the years: Highlights include saying that women who wear Islamic face veils look "like letterboxes" and using racist terms to describe people from the British Commonwealth

But this doesn't extend to the same sort of anti-immigrant rhetoric that we hear so often from Trump. While Johnson has talked about controlling immigration, he is pro-immigration, just as one might expect from the former mayor of liberal, cosmopolitan London. And the idea he would say that British citizens who happen to be an ethnic minority should "go back" if they don't like one of his policies is unthinkable.

Johnson, like Trump, favors lowering taxes for the wealthy. But unlike Trump, he is not an economic protectionist. Johnson believes that one of the main advantages of Brexit is that it will open up the UK's economy to the rest of the world. And, as one might expect from a foreign secretary, Johnson is an unashamed internationalist.

The final and probably most important way that the two men differ is that Johnson actually needs to unite his country. Whatever you think of the man and his politics, Johnson -- unlike Trump -- cannot survive by only playing to his base. If Johnson wants to pull off Brexit and then win a general election in a nation as divided as Britain, he has to win over people from all over the political spectrum. Given that he has wanted this job since he was a child, it is very unlikely that Johnson would use nationally divisive language in the way that Trump does. There simply isn't anything in it for him.

Johnson critics often point to a poster made by the official Leave campaign, which Johnson led, warning of mass immigration from Turkey. The poster was misleading , implying that Turkey would be joining the EU imminently, when it was not. But the point it was making about EU -- that there is free movement through the bloc -- was not incorrect. And it shouldn't be forgotten that Johnson himself has Turkish roots. Whatever your view of this, it's a long way from claiming that you are going to build a wall and make Mexico pay for it.

Another reason Johnson will not like the Trump comparison is that Trump is genuinely unpopular in the UK, according to almost all polling. So, while the President might think that praising Boris and describing him as a friend is the highest of compliments, it could make British voters that are already uncomfortable about their new prime minister even less happy.

A giant balloon depicting US President Donald Trump as an orange baby in London during a demonstration against Trump's visit to the UK on July 13, 2018.

The danger for Johnson is that the harder-line Brexiteers who support him believe that a trade deal with America could be the best way to prove to the world that Brexit was a success project. Therefore, the idea that he will have a good relationship with the President is seen among these people as a positive thing.

But there is absolutely no evidence to suggest that a trade deal with America would make up for the economic damage the UK would suffer if it leaves the EU without a deal. There has been no detail on what that trade deal would be, nor any serious conversations about the fact that Trump is very unlikely to offer an asymmetrical trade deal that floods the UK with dollars.

So, is Boris Johnson the British Trump? They have a similar hairstyle. But that's pretty much where it ends.