Our system is monarchical and unarguably more refined whilst the USA system is more 'Who dares, wins' and to our eyes, there are bound to be glaring differences.
Sadiq Khan is an utter and appalling disgrace in virtually every respect.
In fact...he has no respect.
Donald Trump comes from a country where bluster is more the norm, but whatever his failings re manners, he should never ever be publicly castigated by the Mayor of London.
As for Khan permitting the blimps, that simply shows how low he is.
Sewer level.
I'm certain that the present Mayor of Washington D.C. Muriel Bowser, would never have permitted unflattering blimps of HM Queen Elizabeth to be shown or flown had HM ever made an official visit during her tenure.