Bernie Sanders' plans may be expensive but inaction would cost much more

In Wednesday night’s Democratic debate, the former South Bend mayor Pete Buttigieg charged that the Vermont senator Bernie Sanders’ policy proposals would cost $50tn. Holy Indiana.

Larry Summers, formerly chief White House economic adviser for Barack Obama, puts the price tag at $60tn. “We are in a kind of new era of radical proposal,” he told CNN.

Maya MacGuineas, president of the bipartisan Committee for a Responsible Federal Budget, claims Sanders’ agenda would at least double federal spending.

Putting aside the accuracy of these cost estimates, they omit the other side of the equation: what, by comparison, is the cost of doing nothing?

A Green New Deal might be expensive but doing nothing about climate change will almost certainly cost far more. California is already burning, the midwest and south are flooding, New England is eroding, Florida is sinking. If we don’t launch something as bold as a Green New Deal, we’ll spend trillions coping with the consequences of our failure to be bold.

Medicare for All will cost a lot, but the price of doing nothing about America’s increasingly dysfunctional healthcare system will soon be in the stratosphere. The nation already pays more for healthcare per person and has worse health outcomes than any other advanced country. A new study in the Lancet estimates that Medicare for All would save $450bn and prevent 68,000 unnecessary deaths each year.

Investing in universal childcare, public higher education and woefully outdated and dilapidated infrastructure will be expensive too, but the cost of not making these investments would be astronomical. American productivity is already suffering and millions of families can’t afford decent childcare, college or housing – whose soaring costs are closely related to inadequate transportation and water systems.

Focusing only on the costs of doing something about these problems without mentioning the costs of doing nothing is misleading, but this asymmetry is widespread. Journalists wanting to appear serious about public policy continue to rip into Sanders and the Massachusetts senator Elizabeth Warren (whose policies are almost as ambitious) for the costs of their proposals but never ask self-styled moderates like Buttigieg how they plan to cope with the costs of doing nothing or too little.

A related criticism of Sanders and Warren is that they haven’t come up with ways to pay for their proposals. Sanders “only explained $25tn worth of revenue, which means the hole in there is bigger than the size of the entire economy of the United States”, charged Buttigieg.

Sanders’ and Warren’s wealth taxes would go a long way toward paying for their plans.

But even if it paid a small fraction of the costs of their proposals, so what? As long as every additional dollar of spending reduces by more than a dollar the future costs of climate change, inadequate healthcare and insufficient public investment, it makes sense to spend more.

Republican administrations have doled out gigantic tax cuts to big corporations and the wealthy without announcing specific cuts in public spending or other tax increases because – despite decades of evidence to the contrary – they claim the cuts will generate economic growth that will more than make up for any lost revenue.

Yet when Warren and Sanders propose ambitious plans for reducing empirically verifiable costs of large and growing public problems, they are skewered by fellow Democrats and the press for not having ways to pay for them.

A third line of criticism is that Sanders’ and Warren’s proposals are just too big: they’re risky, they may fail or have unintended consequences, they’ll be difficult to implement.

This argument might be convincing if the problems Sanders and Warren address were growing slowly. But if anything, they’re speeding up. Experts on the environment, health, education and infrastructure are nearly unanimous: these problems are worsening exponentially.

Climate change is upon us; the environment is altering far more quickly than scientists feared even a few years ago. The cost of health insurance is soaring, as are the costs of preventive care. So too with childcare, college and a crumbling infrastructure. And let’s not forget widening inequality, as most families continue to face stagnant wages while wealth and power accumulate at the top.

On all these fronts, the cost of doing nothing is surging. Cautious incrementalism is wise under most circumstances. But where headwinds are turning into a gale, incrementalism drives us backwards. One of the least-acknowledged costs of the Trump years is how far the failure to address these growing problems has set us back.

Dubbing Sanders and Warren “extremists” or “radicals” is absurd when they are seeking to remedy problems which themselves are extreme and will radically harm Americans if left unattended. The status quo is not sustainable.

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Young people understand this, perhaps because they will bear more of the costs of inaction. An Emerson poll of Iowa found that 44% of Democrats under 50 support Sanders and 10% favor Warren. No other candidate reached double digits. In New Hampshire, Sanders won more voters under 30 than the other candidates combined, according to CNN exit polls.

The reason to support Sanders’ and Warren’s proposals isn’t because they inspire and mobilize voters. It is because they are necessary.

We can no longer pretend that climate change, a wildly dysfunctional healthcare system and a yawning deficit in public investment pose insignificant challenges. Doing nothing or doing too little will make them far worse. Obsessing about the cost of addressing them without acknowledging the cost of failing to address them is dangerously irresponsible.

• Robert Reich, a former US secretary of labor, is professor of public policy at the University of California at Berkeley and the author of Saving Capitalism: For the Many, Not the Few and The Common Good. His next book, The System: Who Rigged It, How We Fix It, will be out in March. He is a columnist for Guardian US