The 100-year-period from 1880 to 1980 has seen the inception, unification, division and ultimate destruction of all of Western Europe's Socialist and Progressive parties. Whether in Britain, France, Germany, Italy, Scandinavia, the Iberian peninsula, Greece or the Low Countries, the end of the 20th century sees the Western European Left in comprehensive retreat from its long-term ambitions to overthrow - or at least reform - the capitalist system. Sassoon's main thesis is that far from overthrowing capitalism, socialism has, in the late 19th and 20th century, enjoyed a symbiotic relationship with it. Each has systematically given substantial ground to the other.