Employers are more financially sophisticated. Giving them money to ensure that their workers build up an adequate nest egg is not an unreasonable choice. "Tax credits would directly link worker savings to the company bottom line," he writes, "increasing firms' interest in getting their employees to save."
Under not unreasonable assumptions, Mr. Friedman estimates his proposal could increase the share of private sector workers with retirement savings to at least 65 percent, from 41 percent, mostly among the middle class. By retirement day, a typical working household would have $400,000 in savings, compared to $100,000 today.
That might be enough to buy an annuity of $35,000 a year, which, combined with $25,000 from Social Security, could come close to covering the median household income for a couple. The additional cost to the government, in Mr. Friedman's analysis, would be slight. And government subsidies, today tilted sharply toward affluent workers, would shift toward lower-income workers.
"People who are now coming in with nothing would come in with enough to make a difference in retirement readiness," Professor Freidman said.
Could this be enough?
Prodding workers to save more when real wages have not increased in a quarter-century is not a particularly promising avenue. Conscripting companies to raise workers' savings may help, but it could well fall short.
Maybe the government should do the job.
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At a conference hosted by the International Monetary Fund, Brad Delong, an economist at the University of California, Berkeley, argued that private markets were ill suited to handle the sort of long-term assessments needed to ensure a decent retirement.
"The 21st century will see longer life expectancy, and thus a greater role for pensions," he wrote. "Yet here in the United States the privatization of pensions via 401(k)'s has been an equally great disaster."
Rather than shrink Social Security, some experts and liberal politicians like Elizabeth Warren of Massachusetts and the Democratic presidential candidate Bernie Sanders propose expanding it.
Today, more than half of working households do not have enough assets to avoid a drop in consumption in retirement, according to analyses by Alicia H. Munnell from Boston College and her colleagues. The proportion of households in that group has increased by 10 percentage points in just the last 10 years.
Addressing this challenge would require somewhat higher taxes, tilted toward those most able to afford them, not lower taxes on the wealthy in a fruitless bid to encourage them to invest more. That may seem an uphill battle in today's political climate. But the alternative could prove calamitous. Ignoring the problem will condemn a generation of elderly Americans to the kind of poverty we believed we had eradicated long ago.