That’s the underlying conclusion of an academic paper by former Federal Reserve Chairman Alan Greenspan. The article, which will appear this month in International Finance, a journal edited by my Council on Foreign Relations colleague Benn Steil, reviews a technical datum called corporate long-term fixed-asset investment. Greenspan posits that failure by companies to choose to raise levels of such investment since 2008 is evidence of their concern about an unpredictable and overly activist feder