"More importantly, if the Republican Party made abortion illegal in all cases, it would not only lose a valuable wedge issue that it could keep using every two years but also ignite a powerful social movement."
They could still use it as a wedge issue if it was illegal, just as Dems use it as a wedge issue though it is already legal now. After making it illegal, the GOP could say, for example, "Don't elect Democrat X because he will fight to make re-legalize abortion," etc.
B.
===== "I'm not too worried by hegemony / I know the cadre will look after me" - Magazine, "Model Worker," 1978