In western Europe Roma migrants have faced firebomb attacks in Italy, pogroms in Belfast and forcible evictions in Greece.

ECONOMIST: Europe's Roma

Mrs Friedan determined to write a book, and in 1963 threw a firebomb into American society whose effects are still reverberating.

ECONOMIST: Betty Friedan

Mr Dahmer was killed in 1966 by a firebomb.

ECONOMIST: Race relations