The European left seemed to be in rude health during the 1970s. Never had so many political parties committed to representing the working class been in power simultaneously across the continent. New forms of mobilisation led by female, immigrant, and young wage-earners seemed to reflect the growing strength of the workers' movement rather than its pending obsolescence. Parties and trade unions grew rapidly as a diverse new generation entered the ranks. Why did the left's forward march halt so abruptly?