June marks Pride Month, a time of celebratory parades, parties and rainbow-drenched gatherings all across the United States.

This month also marks the tenth anniversary of the Obergefell v Hodges decision — the landmark US Supreme Court ruling that legalised same-sex marriage in every state. That case, which included several same-sex couples — some with children — ushered in an increased acceptance, visibility and frankly, comfort level among members of the LGBTQ+ community and their families.

In subsequent years, the support for marriage equality ticked up among all groups, most starkly among Republicans who for years ran as defenders of traditional marriage, supporting only unions between one man and one woman.

The trend saw Republican support reach 55 per cent in May of both 2021 and 2022 — a peak, and up from 37 per cent in May 2015 — according to a Gallup poll tracking the party’s alignment with same-sex marriage. But something has shifted in the past few years. As happens with social progress, there has been a concerted and successful backlash to LGBTQ+ equality, driven by conservatives.

Gallup found a clear erosion in support of same-sex marriage among Republicans, with only 41 per cent supporting it today, a 14-point drop in just three years. That decrease dovetails with findings that only 38 per cent of Republicans now say same-sex relations are morally acceptable, down from 56 per cent in 2022. Overall, 68 per cent of Americans support same-sex marriage, including 88 per cent of Democrats and 76 per cent of independents. The path to that level of acceptance took nearly 30 years — in 1996, when Gallup began tracking, only 27 per cent of US adults approved.

But the fight, of course, for LGBTQ+ equality has stretched far beyond three decades — a struggle marked by courage and persistence. Any sign of backtracking threatens to deny LGBTQ+ Americans and their families “equal dignity in the eyes of the law”, to quote Justice Anthony Kennedy, who wrote the Obergefell decision.

The downward trend in support should come as no surprise. The war on “woke” specifically targeted LGBTQ+ people, and not just transgender girls who want to play sport. Gay people, their history, traditions, status and culture have been targeted for erasure, whether in the form of book bans or attacks on drag queen story hour.

The Department of Defence erased images that contained “gay” as a keyword in an effort to purge any trace of diversity, equality and inclusion. Secretary of Defence Pete Hegseth reportedly plans to strip gay civil rights leader and Navy veteran Harvey Milk’s name from a ship. Companies such as Target Corp, once willing to dedicate parts of their stores to Pride merchandise, began a retreat last year fearful of conservative backlash. And several companies scaled back or declined to renew their sponsorship of Pride events this year, as my colleague Beth Kowitt wrote.

Buoyed by the overturning of Roe v Wade, the Southern Baptist Convention voted this month to legally fight to end same-sex marriage, putting the weight of the nation’s largest Protestant denomination behind the effort. Conservative legislators in at least four states, including Michigan and Montana, are pressing the Supreme Court to revisit same-sex marriage, passing resolutions that argue the issue should be left up to states.

The case of Kim Davis — a Kentucky court clerk who refused to issue a gay couple a marriage licence over religious grounds — could make its way to the Supreme Court. A Christian legal group, Liberty Counsel, plans to ask the court to hear her case with the aim of overturning Obergefell, which was decided 5-4.

“At least three sitting Supreme Court Justices [which includes Chief Justice Roberts] expressly wrote that the Obergefell opinion has no basis in the Constitution, meaning we have an excellent chance of overturning the case,” wrote Mat Staver, founder and chairman of the group, in a fundraising letter.

In his 2022 concurring opinion in Dobbs v Jackson Women’s Health Organisation, Justice Clarence Thomas wrote that the court, now dominated by conservatives, should reconsider its prior rulings on same-sex marriage, given that the related case law was built on the same arguments that supported abortion rights. In response, Congress passed the Respect for Marriage Act a few months later, which requires that states recognise same-sex marriages performed in other states.

What that law doesn’t do is require every state to conduct same-sex ceremonies, or explicitly establish marriage as a fundamental right. Conservatives worked for decades to overturn the right to abortion by backing dozens of cases that slowly chipped away at choice, creating a patchwork of laws, some draconian, state by state.

Nearly two dozen states have now banned or severely restricted abortion. Conservatives have signalled they want a similar fight to overturn marriage equality. This time, liberals and supporters of LGBTQ+ rights should take them seriously and fight accordingly to protect marriage as a fundamental right for all.

• Nia-Malika Henderson is a politics and policy columnist for Bloomberg Opinion. A former senior political reporter for CNN and The Washington Post, she has covered politics and campaigns for almost two decades