For contemporary liberals there is no worse offense that to be “against science,” a term that is loosely thrown about to silence skepticism about environmental extremism. But a new study published in the New England Journal of Medicine illustrates that those decrying the effort to oppose late term abortions as a right-wing “war on women” are not only on questionable moral ground but also disregarding scientific facts about premature babies. According to the Journal, it is now clear that babies born at 22 or 23 weeks into pregnancy have a decent chance to survive if given treatment. Those born at 23 weeks are even more likely to live with half doing so without significant problems. This is good news for families but as even the New York Times tacitly admitted in its story about the report, it is bad news for those on the left who have been fighting efforts in state legislatures to ban late term abortions. Given the now incontrovertible fact that babies who are now still being legally aborted could live outside of the womb, the moral rationale for opposing late term bans has disappeared. More to the point, Democrats who have treated opposition to any limits on abortion as a litmus test of support for the rights of women must now come to terms with the fact that their extremism on the issue has led them not so much to defend a right to “choose” as infanticide.

The study illustrates the revolution in prenatal care that has transformed the way we regard pregnancy. When the U.S. Supreme Court decided the Roe v. Wade case that legalized abortion in 1973 it was easier to think of a baby before it emerged from the womb as an abstraction. Expectant parents were not supplied with sonogram pictures of their child early in the pregnancy. Babies born prior to the last month or two of pregnancy had little or no chance of survival. But in the last generation that has changed as the rates of survival for such babies have climbed. Scientific advances have now created a new reality where we now assume a premature infant will survive without complications where once we would have thought there would have been little or no hope. And those that we would not have even considered to have a prayer now have a fighting chance.

This ought to have altered the moral and political landscape on which the issue of abortion is decided. But for much of our political establishment, inconvenient facts such as those put forward by the New England Journal must be disregarded. Instead of coming to grips with the fact that allowing the practice of late term abortion is enabling the slaughter of many babies that could live, they remain in denial. Instead they make national heroines of politicians like Wendy Davis who filibustered a late term abortion bill that would protect the lives of infants that we know might be able to live apart from their mother if given sufficient medical care. Just last month, Rep. Debbie Wassserman Schultz argued that there should be no restrictions on abortion.

It should be acknowledged that the Journal study and the entire question of late term abortions need not alter the debate about abortions that occur early in a pregnancy. While a large number of Americans believe abortion at any point is immoral, there seems to be a broad consensus that such procedures should remain legal. Moreover, there seems little chance that the courts will ever reverse Roe rendering the discussion about banning abortion altogether largely irrelevant to political reality. Nor should this discussion ignore the fact that some abortions, including those that might happen late in a pregnancy, might be dictated by medical necessity to save the life of the mother. But while such instances are real they are rare.

It is also true that many in the pro-choice camp regard efforts to ban late term procedures as the thin edge of the wedge of the pro-life movement effort to gain a toehold before moving on to broader restrictions. They’re probably right about that in the same sense that the National Rifle Association regards any restrictions on gun sales or ownership, no matter how reasonable, to be the precursor of efforts to repeal the Second Amendment and take away the right to bear arms. But just because some would like to ban all abortions that most Americans wish would remain legal does not require us to ignore the facts about late term pregnancies.

In 2013, the nation was reminded of the moral cost of late term abortion when the trial of Kermit Gosnell, a Philadelphia abortion provider, revealed the facts about the way his clinic carried out late term abortions. Gosnell’s abortion mill carried out late term procedures that other doctors refused to do. His facility was not only endangering the lives of the mothers who came to them but murdered babies born alive during late abortions. We were told that Gosnell’s murderous behavior was an exception but when the case prompted a movement to raise the standards at abortion clinics, the pro-choice movement responded with anger claiming such regulations were merely a subterfuge for interfering with abortion rights.

That debate continues but as we head into the 2016 election cycle and there’s little doubt we will be hearing a great deal more about those who wish to ban procedures as waging a war against women. But this latest study should serve as a reminder that the debate about late term abortion isn’t so much about a culture war the left thinks it can win as it is a gap between those who understand that science has forever altered the debate about some kinds of abortions and those who think we must pretend that medicine hasn’t made any progress since 1973. In this case the “deniers” are on the left, not the right.