For roughly 25 years, the movement against abortion has been predominantly incrementalist. Its focus has been on restricting abortion in relatively modest ways rather than on amending the Constitution to prohibit it altogether.

In the 1990s, pro-lifers began to campaign to ban a method of abortion they called “partial-birth abortion.” More recently they have sought to ban abortions after 20 weeks of gestation.

The theory behind this strategy is that changes to the law would reduce abortion rates, and debate over these changes would turn public opinion against abortion. Small victories today would enable bigger ones tomorrow.