Think of this from a different angle: In the 30+ years since Roe, the problem has not been solved without it.
This is a project that takes time to build the required numbers. Once the critical mass has been reached it becomes increasingly entrenched into the culture.
It very well may have worked already if it started in 1973. Among the current students who are in kindergarten through twelfth grade in the U.S., over twelve million are in Protestant schools or Bible study, 6.8 million are in Catholic schools or CCD, and well over one million are being home schooled. And of course it can't happen in public schools.
Also think of the peripheral effects: The number of adults who will be learning and changing and more importantly the kids who share this truth with friends who are in govt schools.
If we could add up the tens of millions of people who would now be pro-life today but for lack of pro-life education are pro-choice--the numbers would be monumental.
A note about politics: Most elections are won by relatively close margins. We only need to shift the percentage of voters a few points to win the extra seats needed for true pro-life legislation.