It is a fact universally acknowledged that yanks can’t do accents of any kind, never mind the elisions & glottal stops of Blighty’s multitudinous dialects/regional & class intonations but have you ever heard a pom try to do amerikan? Makes the ears bleed & teeth ache but, fortunately, enough refugees from Benighted States live in the UK to enable the Beeb to get them cheap for radio plays.