Sean Carroll in Preposterous Universe:
People throughout history have imagined ideal societies of various sorts. As the twentieth century dawned, advances in manufacturing and communication arguably brought the idea of utopia within our practical reach, at least as far as economic necessities are concerned. But we failed to achieve it, to say the least. Brad DeLong’s new book, Slouching Towards Utopia: An Economic History of the Twentieth Century, investigates why. He compares the competing political and economic systems that dominated the “long 20th century” from 1870 to 2010, and how we managed to create such enormous wealth and still be left with such intractable problems.