Today marks the 40th anniversary of the Supreme Court’s decision in Roe v. Wade that overturned state abortion laws and sanctioned abortion on demand across the United States.

Despite the proclamations of supporters that the Court’s pronouncements in Roe and its accompanying case Doe v. Bolton had “settled” the abortion issue, nothing could be further from the truth.

Chuck Donovan, president of the Charlotte Lozier Institute, comments that these cases “remain the ultimate in unsettling law, upending the meaning of the Declaration of Independence and creating conditions where human lives are not seen as created equal in value.”

It’s a decision that has come at an unspeakable cost: Estimates suggest that more than 55 million abortions have occurred since 1973.

Just a few years after the Roe decision, then-President Ronald Reagan recounted the steep toll of the Court’s ruling on society and the future preservation of American values:

Abortion has denied [these children] the first and most basic of human rights, and we are infinitely poorer for their loss. We are poorer not simply for lives not led and for contributions not made, but also for the erosion of our sense of the worth and dignity of every individual. To diminish the value of one category of human life is to diminish us all.

Supporters of the Roe decision have felt the pressing weight of that truth for 40 years. No longer able to convince new generations that denying life to some will lead to greater happiness for others, the philosophy of Roe—like its original champions—isn’t so vigorous today.

Polls indicate that roughly half of Americans identify themselves as “pro-life”—including many millennials, who will make up a significant part of the March for Life in Washington, D.C., later this week.

According to Americans United for Life, at least 60 new pro-life laws were enacted in states across the country last year alone. Thousands of community-based pregnancy centers have harnessed the best of the power and spirit of civil society, providing compassionate counseling, holistic support, and accurate information to women facing unplanned pregnancies.

Since 1973, the pro-life movement’s many foot soldiers have charged the hill of American law and culture to victories so impressive that even Time magazine has recognized that pro-abortion advocates are on the losing side.

Still, the challenges to life, conscience, and freedom that inevitably stem from sanctioned abortion on demand persist.

Every year, the federal government entangles taxpayers in the abortion business, sending hundreds of millions of dollars to Planned Parenthood, which performs one out of four abortions in the United States. Washington also funnels federal aid to a number of international groups that promote and perform abortions—at least one of which has been implicated in abetting China’s coercive one-child policy.

Then there’s Obamacare. The health care law that is wreaking havoc on religious liberty through its anti-conscience mandate also provides weak and limited conscience protections for medical providers and opens avenues for increased individual and taxpayer funding of abortion.

Though these and many other challenges continue to test their resolve, pro-life leaders have a winning strategy that has proven effective in changing hearts, minds, and laws: “Witness to the truth matters for its own sake,” writes Heritage’s William E. Simon Fellow Ryan Anderson on the anniversary of Roe, “but persistent, winsome witness also tends to bear good fruit, even if it takes 40 years and counting.”

With the courageous efforts and continued victories of many leaders in the pro-life movement, hope remains that it won’t take another 40 years for government to respect the conscience rights of individuals, medical providers, and taxpayers and ensure the basic rights of liberty and life for everyone—including those yet to be born.