In 1976, just a few years after the Supreme Court handed down its opinion in Roe v. Wade, most Americans thought abortion should be legal in at least some circumstances.

Those numbers haven’t changed much over almost 50 years. Most Americans still believe abortion should be legal in most circumstances. But our politics have shifted dramatically. Anti-abortion Democrats and pro-abortion rights Republicans are dwindling breeds.

Why? One major reason is a deliberate, decadeslong campaign on the right to overturn Roe v. Wade. Conservative attorneys brought cases that undermined Roe with the hope that, by chipping away at the ruling, Supreme Court justices would eventually feel comfortable striking it down.

The anti-abortion movement has also focused on building a pipeline of judicial nominees through organizations like the Federalist Society. The left, meanwhile, has focused on shifting party opinion on related issues like contraception coverage and the Hyde Amendment, which prohibits government funds from being used to pay for abortion except in the case of rape, incest, or endangering the mother’s life, while treating Roe as a largely settled matter.

Now, all those years of work by anti-abortion activists seem to be paying off. If the Supreme Court overturns Roe v. Wade, as it appears set to do based on the draft opinion that leaked Monday night, it will toss out nearly 50 years of jurisprudence along with it.

Over the decades, the ruling turned into one of the biggest lightning rods in American politics, and those years were punctuated by crucial moments.

Here are the most significant.

1973: Roe v. Wade is decided. Justice Harry Blackmun writes the opinion, finding that people have a constitutional right to an abortion in the first and second trimester. He grounds that right in the 14th Amendment right to due process and an implied right to privacy.

1976: The Hyde Amendment passes for the first time. The measure prohibits government funds from being spent on abortion services except in cases of rape, incest, or threats to the life of the mother. The provision exemplifies the kind of restrictions on abortion that the right continued to champion over the next five decades — and eventually draws the focus of the Democratic Party.

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1978: James Bopp is named the general counsel of the National Right to Life Committee, the nation’s leading anti-abortion group. He becomes the architect of the strategy that looks set to succeed today: an “incremental” approach to slowly undermine Roe until, he hoped, the justices would eventually overturn it. Over the next four decades, Bopp helped states and localities draft abortion restrictions and, when those restrictions were challenged, defended them in the courts. Bopp also wrote the anti-abortion plank for the Republican Party platform in 1980.

1980: A new alliance between Catholics and evangelicals, driven in part by opposition to abortion, helps Ronald Reagan capture the Republican nomination and, eventually, the presidency. It’s the first time abortion becomes a salient national political issue since Roe — and that’s in part because evangelical leaders saw it as a more politically palatable issue than their true concerns: maintaining segregation in schools. Still, the alliance, known as the Moral Majority, becomes a political force to be reckoned with for years to come, and elevates the anti-abortion cause and religious right.

1992: The Supreme Court decides Planned Parenthood of Southeastern Pennsylvania v. Casey, a case concerning state-level abortion restrictions in Pennsylvania. Roe survives, but in this first serious test for abortion rights since it was decided, the Court establishes new limits on the right. In a 5-4 decision, the Court declares that states can pass abortion restrictions as long as they don’t pose an “undue burden” on the pregnant person and replaces the trimester framework with a “viability” of the fetus standard. Following these new standards, the Court upholds most of Pennsylvania’s restrictions.

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2006: Cecile Richards becomes the president of Planned Parenthood. It’s a deliberate move to select a leader suited to build the organization’s political power throughout the country and within the Democratic Party. Richards organizes the group’s local chapters and capitalizes on political events in 2010 and 2011 so that Planned Parenthood becomes a force in the Democratic Party — so much so that in 2012, the party included a declaration of support for Planned Parenthood in its platform.

2009: Dr. George Tiller, a Kansas abortion provider, is murdered while serving as an usher at his church. It’s the most extreme example of the rise in violent acts by anti-abortion activists.

2010: In March, President Barack Obama signed the Affordable Care Act into law. Because Obama needed the support of even pro-life Democrats to pass it, the bill included a compromise on abortion, the Boxer-Nelson Amendment. It allowed states to prohibit plans in the insurance marketplaces from covering abortion. President Obama also signed an executive order declaring that the Hyde Amendment applied to the ACA, and abortion rights activists responded by creating a coalition to defeat the Hyde Amendment.

That fall, the Republican Party sweeps the midterm elections, thanks, in part, to backlash to the ACA and the rise of the Tea Party movement. The following year, states pass a record number of abortion restrictions.

2011: The US House passes an amendment by then-Rep. Mike Pence to defund Planned Parenthood. Though the amendment does not pass the Senate, it becomes a polarizing force between the parties.

Abortion rights organizations capitalize on the amendment and the Tea Party’s broader effort to defund and restrict abortion rights: Online gifts to Planned Parenthood increased by 500 percent, and NARAL’s email activist list grew by 1,000 subscribers per day at the height of the debate around Pence’s amendment.

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2012: The DNC pushes an abortion rights message at the national convention. The organization includes a new paragraph in its party plank:

The President and the Democratic Party believe that women have a right to control their reproductive choices. Democrats support access to affordable family planning services, and President Obama and Democrats will continue to stand up to Republican efforts to defund Planned Parenthood health centers. The Affordable Care Act ensures that women have access to contraception in their health insurance plans, and the President has respected the principle of religious liberty. Democrats support evidence-based and age-appropriate sex education.

2016: Thanks, in part, to the movement that started after the ACA in 2010, Hillary Clinton and Bernie Sanders call for repealing the Hyde Amendment in their presidential campaigns that spring. The DNC eventually adopts that language for its party platform.

Come November, however, Donald Trump is elected president and effectively delegates judicial selection to the conservative Federalist Society. He nominates three Supreme Court justices during his term in office: Justices Neil Gorsuch, Brett Kavanaugh, and Amy Coney Barrett.

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2019: As laws that would ban abortions after the sixth week spread across the US, Democratic presidential candidate Joe Biden endorses the repeal of the Hyde Amendment on the campaign trail. As president, he will attempt to make good on his promise; his first budget proposal reversed the Hyde Amendment, though Congress, which ultimately holds the power of the purse, overruled him.

2020: Liberal Justice Ruth Bader Ginsburg dies of cancer less than two months before the presidential election. Trump and the Republican Senate quickly confirm the Federalist Society-endorsed Barrett, giving conservatives a 6-3 supermajority on the Court and prompting anti-abortion groups to tee up state laws restricting abortion that would invite challenges and a showdown in the Supreme Court.

2021: Dobbs v. Jackson Women’s Health Organization, a case concerning a Mississippi law that bans abortion after 15 weeks, is argued at the Supreme Court. The conservative litigants explicitly ask the Court to overturn Roe, and the justices indicate they are open to doing so.

2022: Justice Samuel Alito’s draft majority opinion in Dobbs is leaked to Politico and confirmed as authentic, though not final. The opinion, if it holds, would overturn Roe v. Wade, leaving abortion rights up to the states, unless Congress steps in and passes a national policy.

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