On January 22, 1973 the United States Supreme Court in the case of Roe v. Wade and in the companion case of Doe v. Bolton made up a Constitutional right to abortion out of thin air. There was nothing in the Constitution forbidding the states from regulating abortion, and the states had so regulated, and often criminalized, abortion since the inception of the Republic. Roe and Doe were terrible crimes against the unborn, but they were also blows against the most precious civil liberty Americans possess: the right to rule ourselves.
If Roe were overturned, the abortion regime of abortion on demand would be limited to a handful of states. Some states would ban abortion outright in almost all cases. Most would bring abortion under ever growing restrictions that would shrink the number of abortions performed. One of the prime defenses of abortion currently, that is a Constitutional right, would be no more. Pro-lifers would be free to focus on the ugly reality of abortion without fear that Federal courts by judicial fiat would upend hard won pro-life legislation at the state level.