“If you widen the lens, the public is being sold a big lie — that our problems owe to unions and the size of government and not to fraud and deregulation and vast concentration of wealth. Obama’s failure is that he won’t challenge this Republican narrative, and give people a story that helps them connect the dots and understand where we’re going.”

Mr. Reich, 64, is one of several prominent liberal economists who despair of what they say is this president’s political caution, and his unwillingness to duel with an emboldened Republican Party…

The modern Democratic Party, he says, is removed from what he and Mr. Krugman view as a better time: the decades stretching from World War II until about 1970. The typical high-income earner then paid more than 50 percent of income as taxes. The economic bargain was explicit: government encouraged industry, and working Americans shared in the fruits, buying houses and cars, with pensions to tide comfortable retirements.

“We tend to think of the political center as static, but it’s become much more conservative over time,” Mr. Reich says. “What’s happened in the last 30 years is that the private sector worker has taken a shellacking.”