History is an uncertain guide to the future. We may say that a strategy that succeeded under a certain set of conditions in the past will lead to similar outcomes in cases with similar conditions today. But, in reality, conditions are never fully the same and are constantly changing: global and national opportunity structures shift, dominant ideas concerning development and the economy rise and fall, technological innovation and political organization transform the balance of class forces, and well-organized progressive parties with far-sighted leadership emerge – or fail to emerge. Politics is the art of the possible, but it is never entirely clear in advance what constitutes the realm of the possible. Leadership and political vision are thus critical determinants of success.

Historical experience is more useful in offering warnings about what to avoid than “lessons” for successful action. The debacles of socialism and social democracy in the twentieth century suggest two warnings. First, to the extent possible, democratic means are required to reach democratic ends: means and ends cannot be separated. This requirement undoubtedly places onerous restrictions on regimes attacking inherited privilege. Warding off hostile domestic elites and the external defenders of the existing economic order is a major challenge for democratic redistributive regimes. But there is little choice for movements truly struggling for equal freedom. Justifying extra-legal, authoritarian means on the grounds of self-defense is to start the slide to tyranny. Also, markets appear indispensable in modern economies. Central planning doesn’t work, and participatory planning at the national level (though as yet untested) seems impractical.