I suspect that TM made BJ Foreign Secretary in order to give him enough rope to hang himself - or not.
It is a bit like the election of Jeremy Corbyn as Labour leader. BJ may take us all by surprise and prove to be a subtle and clever Foreign Secretary. On the other hand, like JC, he may simply prove how unsuited he is for any position of responsibility.
I notice that he was booed at the French Embassy last night.
I would love Boris to step up to the plate and do a good job as FS. He speaks 4 languages, is well travelled and is highly intelligent IMO, when he is not play in the fool. He has something of the naughty schoolboy about him.
There was speculation (and it WAS speculation) that May was being Machiavellian in her appointment of Bojo. Kind of saying "you wanted Brexit-now get on and deal with it" to Bojo whilst handing the real brief to Fox and Davis.
Ie handing him the rope with which to hang himself.
Having lived in scientific circles most of my life, I am only too aware that intelligence is not necessarily associated with common sense. Boris Johnson seems to work on the principle that 'charm' will cover any blunders he makes. It doesn't. On a wider topic, we now have people in the higher echelon of power who: are serial adulterers; have shown confidential government documents to a friend; and someone who apparently believes male nannies are paedophiles. At least we are spared the one who thinks gay people can be cured
We do need clever mavericks who can think 'out of the box' but they need to be supported by a host of sensible doers. I just hope the FO contains plenty of those.