Over the past century, there has been a characteristic American cycle of response to far-reaching social reforms.

When the breakthroughs are first proposed, conservatives fight them with a devout passion, warning that the measures on offer would move the nation toward socialism and perdition. Then, over time, the disastrous consequences never materialize, the reforms prove their worth, and Americans come to see the once-new benefits as rights.

This was certainly the case with two of our nation’s greatest social programs.

In the debate over Franklin D. Roosevelt’s plan for Social Security, Rep. James Wadsworth said the system would make government “so vast, so powerful as to threaten the integrity of our institutions and to pull the pillars of the temple down upon the heads of our descendants.”

Rep. John Taber, like Wadsworth a conservative Republican from New York, was equally apocalyptic: “Never in the history of the world has any measure been brought here so insidiously designed as to prevent business recovery, to enslave workers and to prevent any possibility of the employers providing work for the people.”

(Bastien Inzaurralde/The Washington Post)

As it happened, the pillars of the temple remained firmly in place, and so today does Social Security.

The story is the same with Medicare. An eloquent conservative actor named Ronald Reagan warned in 1961 that if the plan passed, “behind it will come other federal programs that will invade every area of freedom as we have known it in this country.”

Reagan saw only darkness ahead if Americans did not rise up against this scheme. “One of these days, you and I are going to spend our sunset years telling our children, and our children’s children, what it once was like in America when men were free.”

The Gipper also offered this: “It’s very easy to disguise a medical program as a humanitarian project. Most people are a little reluctant to oppose anything that suggests medical care for people who possibly can’t afford it.”

As well they should be, and this is why the coming weeks will be among the most important in the history of American social policy. A handful of Republican senators will decide whether the Affordable Care Act (ACA) will remain part of the fabric of our nation’s life, the latest in a long series of steps toward a more humane society.

The Obamacare repeal bill unveiled last week by Senate Republican leader Mitch McConnell after the failure of his first try is, if anything, worse than the original, primarily because its insurance “reforms” (really a rollback of the ACA’s actual reforms protecting those with preexisting conditions and limiting premiums for older Americans) would render coverage unaffordable for millions of citizens who face the most severe health problems.

In the meantime, the bill keeps the worst aspect of the earlier GOP draft in place. Sen. Susan Collins, a Maine Republican, bravely and correctly identified the “still deep cuts to Medicaid” as the central reason this bill deserves to die. Because Sen. Rand Paul (R-Ky.) also said he would vote no and the 48 members of the Democratic caucus are prepared to oppose McConnell’s bill, only one more Republican vote is needed to continue our nation’s painfully slow but necessary march toward guaranteeing every American health insurance.

Here’s a suggestion to Dean Heller, Rob Portman, Shelley Moore Capito and Lisa Murkowski, Republican senators who should feel morally bound to vote no. Like Collins, they have spoken strongly against damaging cuts to Medicaid. If they announced their opposition together, they would lessen the political risk of standing alone and create a critical mass of GOP senators who could join Collins in her declared intention of working with Democrats “to fix flaws” in the ACA.

That’s the other thing about enduring social reforms: They have lasted not only because they demonstrated their value, but also because Congress improved them over the years. Social Security, for example, is better because of changes made in the 1950s and 1970s.

To oppose this wretched Senate repeal bill thus does not mean declaring that the ACA is perfect. (Exempt the Ten Commandments if you will, but no legislation is perfect.) It means accepting that Obamacare moved the nation in the right direction — and, by the way, used some conservative ideas to do it.

We can be grateful that earlier generations ignored those who regularly equated social advances with oppression. As Reagan might say, our children and our children’s children will ask whether we shared the courage of our forebears.

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