The anti-abortion “March for Life” for decades demonstrated to Republicans that they could not reach the Oval Office without the support of the anti-abortion movement.

On Friday, marchers will gather in Washington with a decades-long mission accomplished, after the Supreme Court’s removal of a constitutional right to an abortion by overturning the Roe v. Wade decision last year.

That means this year’s march will be a time for celebration but also of debate about where the movement goes next with some campaigners seeking to restrict the procedure everywhere. But such a refocused goal carries big risks. Democrats after all belatedly leveraged their own energy over abortion in the midterm elections in a backlash against the right-wing Supreme Court majority that helped stave off a big Republican midterm election wave.

The March for Life also comes at an extraordinary moment when Donald Trump, the president who did more than any other to end Roe after a pact with social conservative voters that helped win him the 2016 GOP nomination, has launched an extraordinary attack on evangelical leaders he sees as insufficiently loyal, as CNN’s Gabby Orr, Kristen Holmes and Kaitlan Collins reported this week.