Is supporters' belief enough to sustain new PM?

Boris Johnson's political inheritance has all the makings of a disaster.

He has no Commons majority. There is no mandate from the general public - remember this election has only been decided by Tory members.

There are policy problems everywhere in sight - whether that's trying to solve the conundrums of Brexit with a reluctant EU and a divided party or trying to address some of the deep-seated problems at home.

And just as among his fans there is genuine excitement that he will, at last, be in Number 10, there is scepticism and disbelief from the opposition parties, and double-sided concerns in his own party.

There is anxiety on one wing of the Tory party that he will pursue a rapid Brexit and cravenly, hang the consequences of what might be at risk.

But in darker moments on the right of the Tory Party, there are suspicions that underneath the Brexit bluff there's a metropolitan wet, who could betray them. Their man for now, but a prime minister who needs to be strapped into place.

For those who know him best though, the point about Boris Johnson is that he, frustratingly even to them, can be, maybe even wants to be more than one thing at the same time.

They hope he could be a canvas on which others project their hopes and aspirations. A leader who can use his panache to manage all of those competing interests.

A leader who will not be bowed by upsetting one side or another. An incoming prime minister who, in dramatic contrast to Theresa May, can communicate his will to the public and his party, his conviction to get this done.

His plans for the Cabinet, to appoint a record number of women, a record number of ethnic minority MPs, and to promote the next generation, a contrast to the image held by some Conservatives who see him as the one to recreate perceived glories of the past.

And his fans are often willing to accept whatever he actually says or does because the mistakes, or promises come from his lips.

For them perhaps, the belief is in him, beyond actions he takes.

Belief is a powerful commodity but it doesn't preserve a government on its own. For many of Mr Johnson's critics the jokes are old already. For those worried about Brexit, a rousing speech just doesn't solve it.

To govern is not to make people feel good, it is to choose. And as soon as the decisions actually get made, Mr Johnson might find that like Theresa May he finds himself in stalemate.

So sprinkle salt on vows made now about going to the country to ask all of us for his own mandate. Willing success is not the same as delivering it. Ultimately, Boris Johnson will have more than his party to convince.

BBC News 2019