I think they’re right about that, too. Lawrence Summers, the former Treasury secretary, has a nice framing. He says that the late 1960s and the 1970s should have moved a reasonable person to the right on economic policy, in response to rampant inflation, rising crime, sky-high top tax rates and breakdowns in Europe. The last 15 years — with “widening inequality, financial crisis, zero interest rates, rising gaps in life expectancy and opportunity,” as Summers notes — should move that same person to the left. Different eras require different solutions.

Fortunately, policy experts have begun working on those solutions. One possibility is a federal jobs program, putting people to work earning $15 an hour on vital projects like infrastructure and child care. Senator Kirsten Gillibrand, who seems to be eyeing a presidential run, favors an ambitious version called a federal jobs guarantee.

Another option is a strong response to growing corporate power and consolidation. The Open Markets Institute and Roosevelt Institute have sketched out new antimonopoly policies. Other economists are talking about something called wage boards, where companies and workers would negotiate over industrywide pay. Such boards already exist in New York, California and Australia.

On health care, there are proposals to open Medicare to people younger than 65 (which could also reduce health spending). On child poverty, two senators have proposed a $3,600-a-year annual allowance for children under 6. On education, states and cities have created free pre-K or community college. And to help pay for it all, experts are studying how best to raise taxes on the wealthy — who can certainly afford to pay more.

The details will be important. Done wrong, any of these ideas could fizzle. They could make people lose even more faith in government. Done right, though, the ideas could mimic the grand successes of government: Social Security, Medicare, the military, the Securities and Exchange Commission, the highway system, public universities, medical research and a Defense Department project that became the internet.

It’s time to dream big again.