James Pethokoukis warns National Review Online readers that the philosophical fight between capitalism and Marxism — resolution of the Cold War notwithstanding — is far from over.

“Karl Marx wasn’t wrong, just early. Pretty much. Sorry, capitalism. #inequalityforevah”

When trying to condense a sweeping, 700-page analysis of the past, present, and possible future of capitalism into an 85-character tweet, you’re bound to miss a few things. But the above Twitter-fication of economist Thomas Piketty’s much-awaited Capital in the Twenty-First Century captures the gist of the author’s argument.

Piketty thinks the German progenitor of Communism basically got it right. It’s only that his essential insight — private capital accumulation inevitably leads to the concentration of wealth into ever-fewer hands — took a hiatus during the middle part of the last century thanks to depression and war hurting the fortunes of the well-to-do. But now Marxism’s fundamental truth is reasserting itself with a vengeance, a reality borne out in both Piketty’s own meticulously gathered data and in business pages replete with stories of skyrocketing wealth for the 0.001 percent and decades of flat wages for everyone else. …

… Two observations: First, Piketty’s case, though well argued, is far from airtight. He makes a number of contestable assumptions, including a) output will grow more slowly than the return on capital, b) the return on capital will stay high despite slower growth, and c) skyrocketing corporate pay doesn’t much reflect how technology and globalization have enabled top executives to manage or perform on a larger scale.

Second, Piketty and fellow French economist and University of California, Berkeley, inequality researcher Emmanuel Saez are arguably the most important public intellectuals in the world today. Their research is driving the economic agenda pushed by Washington Democrats and promoted by the mainstream media. The soft Marxism in Capital, if unchallenged, will spread among the clerisy and reshape the political economic landscape on which all future policy battles will be waged. We’ve seen this movie before.

John Maynard Keynes and Friedrich Hayek famously squared off in the 1930s, Left versus Right. But when Keynes published his revolutionary General Theory in 1936, Hayek went silent. It was a de facto retreat that helped give free rein to anti-market forces — even if that was not what Keynes intended — for decades until Milton Friedman and Anna Schwartz wrote A Monetary History of the United States in 1963 and energized the intellectual fight against statism.