Ralph Miliband’s Parliamentary Socialism became a standard reference point for debates about the British Labour Party as soon as it first appeared in the early 1960s.

When Miliband published a new edition of the book in 1972, he rejected the idea that Labour might one day become “a party seriously concerned with socialist change.” There was, he acknowledged, no other left-wing organization capable of challenging Labour’s dominant position. But that was “no reason for resigned acceptance or for the perpetuation of hopes which have no basis in political reality.” The first step toward building an alternative force would be “the dissipation of paralysing illusions about the true purpose and role of the Labour Party.”

While Parliamentary Socialism was a hugely influential book, its political conclusions went firmly against the grain. In a response to Miliband, Ken Coates insisted that the future of the British left would have to pass through the Labour Party, one way or another: “Once the workers’ movement in any country has developed its organizations, these bodies will always stand between the articulation of any new ideas and their realization. Unless the mass organizations can be won over, or seriously divided in the course of an attempt to win them over, they will effectively bar the way to the emergence of any alternative.”