Abortion access in America is hanging by a thread. On Wednesday, I sat in the US supreme court and listened to the case – June Medical Services v Russo – that could be the beginning of the end of Roe v Wade.

As the president of the Planned Parenthood Action Fund, it was my privilege to be one of the few listening in the court – but the reality is that this case will affect the rights and lives of millions.

If the court upholds the medically unnecessary Louisiana law at the center of the case, it could leave 1 million women of reproductive age in Louisiana with only one health center that provides abortion. Nationwide, the impact could reach even further: this decision could pave the way for states to in effect ban abortion for more than 25 million women across the country.

The supreme court already ruled – just four years ago – that a nearly identical law was unconstitutional. The only difference now is the composition of the court: Justice Anthony Kennedy, who voted to strike down the law, has retired, and now the justices Brett Kavanaugh and Neil Gorsuch sit on the court.

It’s not by accident that the supreme court is in a position to jeopardize abortion for millions of people. This happened by design.

For decades, anti-abortion politicians have worked to take away our right to control our bodies and access basic healthcare. Five states have only one healthcare center that provides abortions, forcing women to travel hundreds of miles to see a provider. Medically unnecessary laws can require patients to wait up to three days between their first appointment and going in for the procedure – but taking that much time off work, or finding childcare for two trips to the clinic, often makes jumping through those hoops impossible.

And abortion is just one piece of the picture. At the same time as anti-abortion politicians have been pushing these harmful state policies, the current administration has been carrying out a full-throated attack on our reproductive health. Officials have tried to make it harder to get birth control by gutting the only national program for affordable birth control, known as Title X; tried to destroy the Affordable Care Act, which granted tens of millions of women access to birth control without a copay; and given bosses and universities permission to deny their employees or students insurance coverage for birth control for any “moral” reason. In fact, the supreme court will be taking up two of those issues later this year – in cases about access to birth control coverage and healthcare coverage for millions.

To be sure, the fight for access to reproductive healthcare started long before the current administration. Roe v Wade has not ensured that access to abortion is equitable in this country. For people of color, and black women in particular, the promise of reproductive freedom has never been fully realized. Our country’s history of structural racism and discrimination has meant many people of color have less economic opportunity, and with it, less access to healthcare and health insurance.

It’s not an exaggeration to say that the stakes for our reproductive rights have never been higher. If this administration and their allies have their way, millions of people could lose access to birth control and to safe and legal abortion.

To the politicians who aim to rob us of justice – brace yourselves for the strength of our resistance

The irony is that this is all happening against the will of the American people. The vast majority – 77% – of Americans support Roe v Wade. There is no state where the prospect of banning abortion has popular support. Americans want access to birth control, and they want more access to healthcare, not less. These are everyday issues that affect our lives: nearly one in four women in this country will have an abortion. Nearly all women who have had sex have used birth control.

We cannot stop fighting for everyone’s right to access sexual and reproductive healthcare. That means battling efforts to overturn Roe v Wade and criminalize abortion. But it also means diminishing the gap between what is a legal right and what is accessible; legal abortion means nothing if only the privileged have access. Together, alongside our reproductive justice partners on the ground, we must fight state by state to protect access where it still exists, and to expand access where we can.

We have no choice but to fight for justice. We cannot be free to imagine a better world for ourselves, for our children, for our brothers and sisters and non-binary siblings, if we don’t have justice. As Justice Ruth Bader Ginsburg has said, quoting Thomas Jefferson: “When injustice becomes law, resistance becomes duty.”

To the politicians who aim to rob us of that justice – brace yourselves for the strength of our resistance.