Walter Williams, the George Mason University economist, likes to tell the story of the Welcome Wagon visit he and his wife received when they moved to Valley Forge, Pa. The welcomer spoke enthusiastically about the area’s many civic groups and activities, offered recommendations for nearby shops and restaurants, and gave them a packet of coupons for local businesses.

Then she offered voter registration cards. “No thanks,” Williams told her. “I don’t vote. It’s a waste of effort.”

Stunned, his visitor responded, “But Dr. Williams, what if everyone thought that way and didn’t vote?”

“Then,” Williams sagely replied, “I’d vote.”

This primary season, many people who usually don’t vote are heading to the polls to cast ballots for one of two unconventional presidential candidates: Donald Trump or Bernie Sanders. The two have much in common: They hold similar views on immigration[1], trade[2] and entitlements.[3] They both have personalities that can politely be described as prickly. Neither is an accomplished policymaker: Trump has never held office, while Sanders has little to show for his quarter-century on Capitol Hill.

Most important, both candidates have tapped into many Americans’ feelings of economic vulnerability and frustration with politics. They’ve identified public enemies (immigrants, the 1 percent, China, Wall Street, the establishment) and offered simple solutions (build a wall, raise taxes, increase government spending, break up the banks, deport illegals).

Both candidates reject a set of bipartisan economic principles that U.S. policymakers embraced from the mid-1970s to 2000. Those principles—call them the Washington consensus—produced two of the longest periods of economic growth in the nation’s history, the booms of the 1980s and 1990s, separated by one of the nation’s shortest and mildest recessions.[4]

The principles’ origins date back to John F. Kennedy’s administration, when it became apparent that New Deal–era economic policies were faltering. Under the New Deal, government protected a minority of businesses and workers from competition in the hope that their prosperity would buoy others. But politicians and bureaucrats proved ill-suited to manage the many sectors of the American economy. And the protected businesses and workers preferred to enjoy the comforts of their privileged status rather than behave as nimble, innovative competitors. That left other businesses and workers—and American consumers—to bear the costs of the poor management and privilege.

After World War II, with the rest of the developed world’s productive capacity in ruins, the U.S. economy grew despite the New Deal policies. But that couldn’t continue once the other countries recovered. Instead, from the late 1960s to the early 1980s, America suffered waves of inflation, unemployment, and economic stagnation.

Hence the Washington consensus: Government would no longer protect privileged businesses and workers; they’d succeed or fail depending on whether they operated efficiently and satisfied consumers. Freer trade would be permitted, giving American consumers and producers greater access to the world’s productivity. Government spending and budgeting would be more responsible. Welfare recipients would face both incentives and obligations to find work. Tax rates would return to reasonable levels.

Of course, policymakers didn’t always follow those principles. But the violations were usually minor and often undertaken as political theater: relatively small changes in tax rates and minimum wages; short-lived trade barriers.

The United States wasn’t alone in adopting these principles; they spread to much of the developed world. And people have benefited overall. In the United States, unemployment fell to unprecedented levels. All sorts of products that were once reserved for the rich and privileged—advanced telecommunications, airline travel, a diversity of broadcasting, more convenient and extensive banking services, access to different foods and other products—have become commonplace. Most important, the collapse in American living standards that experts were predicting never happened.

But though the consensus was generally good for Americans, it wasn’t flawless. Competition—whether foreign or domestic—is disruptive and economic shocks are painful. Unfortunately, Washington leaders have offered few policy ideas consistent with the consensus that would help people deal with those vulnerabilities. Instead, beginning with George W. Bush’s administration, federal policy has moved away from the consensus: expanding public spending, growing public debt, and increasing government intervention in the economy.

Whatever their intentions, Trump and Sanders’ policies threaten to return America to the 1970s Great Stagnation. The country’s next leaders should, instead, restore and improve on the Washington consensus, giving people both more economic growth and more economic security. The other major presidential candidates may be able to accomplish that: Hillary Clinton is married to one of the top consensus practitioners; John Kasich contributed to it during his years in Congress; and Ted Cruz talks of returning to the policies that fueled the economic boom at the end of the last century.

If one of those candidates could restore that prosperity, it would make voting worthwhile.

Thomas A. Firey is a senior fellow with the Maryland Public Policy Institute (www.mdpolicy.org) and a Washington County native.