For close to forty years—ever since Roe v. Wade, in 1973—Republicans have been battening on the “pro-life” movement and getting away with it. Even though, then as now, three-quarters of the public has believed that abortion should at least sometimes be legal, the Party line has moved steadily toward theocratic absolutism. The platform currently under construction in Tampa calls for total criminalization, including under circumstances of rape, incest, and lethal danger to the woman concerned. Until this week that was Paul Ryan’s position, too; now, post-Akin, he says he would accept a rape exception. This puts him on the same blotted page as Mitt Romney, who launched his political career claiming to be as pro-choice as Ted Kennedy. Extremism is the new moderation.

The G.O.P. has never had to pay anything like the full political price for its abortion gamesmanship. The reason is Roe v. Wade. Republican legislatures and Republican Congresses have passed plenty of laws aimed at making it functionally impossible, prohibitively expensive, or psychologically humiliating for poor or near-poor women and girls to get abortions. Because of Roe v. Wade, though, Republican politicians could pound the “pro-life” podium without worrying that the wives and daughters of their friends and contributors might similarly suffer. Because of Roe v. Wade, there was never much danger that a woman of means would have serious trouble arranging a safe, discreet end to an unwanted or dangerous pregnancy. If she thought that her marginal tax rate was too high, she could vote Republican secure in the knowledge that her right to choose would not be affected. The Supreme Court would protect her from Akin and his ilk.

What’s different this time is not just that the ilk of Akin now includes pretty much every Republican holder of or aspirant to public office. Nor is it that even a Tea Party President and Congress could actually muster the votes to make abortion a federal crime. It’s that the Supreme Court isn’t what it used to be. The flames are threatening to jump the Roe v. Wade firewall. In 1973 the vote was 7 to 2. Now, eight Republican and four Democratic appointments later, it’s down to 5 to 4. A Romney appointment could make it 4 to 5. Until Todd Akin came along, no one was paying much attention. Now, thanks to Akin, it may be possible for the tocsin to be heard.

Photograph by Jeff Roberson/AP.