From a tidy glass office in Midtown Manhattan, Darren Walker gives away US$650 million ($970m) a year of other people's money, and is paid nicely to do so. When he got this job in 2013, as president of the Ford Foundation, he set his sights on tackling inequality.

There were complications.

Charities like Ford, he realized, owe their existence to inequality, and they reproduce it: they extend rich people's influence, with no accountability, and they take money from the public tax rolls to do so. If a foundation gives a million dollars to a donor's favorite pet cause, part of