Jim Bourg / Reuters

President Trump has nominated Brett Kavanaugh to be the next U.S. Supreme Court justice. In a televised announcement on Monday night, he said that Kavanaugh is “a judge’s judge,” with “impeccable credentials, unsurpassed qualifications, and a proven commitment to equal justice under the law.”

“What matters is not a judge’s political views,” Trump said, “but whether they can set aside those views and do what the law and Constitution require.” The president also called for a swift, bipartisan confirmation in the coming weeks, and called the rule of law “the cornerstone of our freedom.”

The president isn’t likely to get the speedy process he’s hoping for. Democratic politicians and liberal advocacy groups are gearing up for a fierce fight, hoping to extend confirmation hearings until the midterm elections or beyond. For decades, Justice Anthony Kennedy was a conservative, swing-voting justice; in his absence, the Court is likely to move decisively right. Liberal and conservative groups are both hoping to mobilize their core supporters in the fight for or against Kavanaugh’s nomination. As they look toward the midterms, these groups have already begun spending lots of money on ad campaigns targeting the moderate senators whose votes will be most crucial in the confirmation process.

Ultimately, the stakes of this nomination go well beyond 2018. This Supreme Court appointment could shape the federal judiciary for a generation. If Kavanaugh is confirmed, he will likely serve as a staunch conservative, originalist voice on the Court for decades to come, establishing a renewed conservative majority that could fundamentally reshape a range of legal areas, especially when it comes to hotly contested social issues like abortion and LGBT rights.

Kavanaugh has served on the D.C. Circuit Court of Appeals for more than a decade, and during that time, he has weighed in on a number of consequential cases. Last fall, he dissented from a ruling that allowed an undocumented teen to seek an abortion, saying that the majority had “badly erred.” Several years ago, he dissented in another case involving Priests for Life, one of the groups that challenged the birth-control mandate in the Affordable Care Act on religious grounds. As Edith Roberts writes over at SCOTUSblog, the legal website, his biggest impact has perhaps been in checking administrative power, especially at the Environmental Protection Agency.

In some ways, Kavanaugh would be continuing Kennedy’s legacy on the Court. He clerked for the justice in the early 1990s, and Kennedy swore Kavanaugh in to his post on the D.C. Circuit in 2006. He’s got a long resume in Republican politics: He worked with the attorney Kenneth Starr on the investigation into the death of Vince Foster, an aide to President Bill Clinton, and on the Starr Report, which laid out the case for Clinton’s impeachment. He is both a George W. Bush appointee and a family friend: His wife, Ashley, was the former president’s personal secretary for years.

Like Neil Gorsuch, Trump’s last pick for the Supreme Court, Kavanaugh is in his early 50s, meaning he would likely have a long tenure on the Court. And that is exactly what worries liberal activists.

Almost as soon as Kennedy announced his retirement, political groups turned the fight over his replacement into a fight over abortion. Although Kennedy was not yet on the Court in 1973 when Roe v. Wade established women’s right to an abortion, the justice famously provided the crucial fifth vote in the 1992 case Planned Parenthood v. Casey, which reaffirmed the legal framework laid out in Roe. Throughout his tenure, Kennedy largely continued to support fundamental abortion rights—within limits, which made him unpopular among both pro-choice and pro-life activists.

Since the beginning of his campaign, Trump has been promising to use judicial appointments to overturn Roe, which would theoretically send the question of abortion access back to state legislatures. During a 2016 Fox News interview, the president said Roe would be overturned “automatically” if he’s able to appoint two or three new justices, “because I am putting pro-life justices on the Court.” He recently told Fox News’s Maria Bartiromo that “Roe v. Wade is probably the one that people are talking about in terms of having an effect.”

Pro-life activists have been thrilled by Trump’s support for their cause. These groups have been intimately involved in crafting the strategy around this nomination—everything from floating potential names to planning a campaign to secure confirmation votes.

Meanwhile, pro-choice groups are using Trump’s words to activate the liberal base and put pressure on vulnerable senators. NARAL Pro-Choice America, a political advocacy group in D.C., has been targeting Senator Susan Collins, who said in a recent interview that a Supreme Court nominee who would overturn Roe “would not be acceptable.” Last week, the group ran print and digital ads across Maine, Collins’s home state. “Trump has been loud and clear in saying he’d pick Supreme Court Justices to end Roe v. Wade,” they said. “We believe him. Don’t you, Senator Collins?” Ahead of Trump’s announcement, Planned Parenthood circulated documents with background information on each of the four possible nominees Trump considered, highlighting ways in which they had ostensibly demonstrated hostility toward legal abortion.

But abortion is far from the only issue that will likely be shaped by the next Supreme Court justice. Kennedy may be best remembered for his slow campaign to expand LGBT rights, culminating in the legalization of same-sex marriage in Obergefell v. Hodges in 2015. While the Court has laid a clear foundation for certain LGBT rights, many questions—about public accommodations for transgender students, housing and employment discrimination, and more—are still unresolved. A definitively conservative Court has the potential to slow or reverse the last few decades’ steady expansion of LGBT rights, which has often been driven most powerfully by the judiciary.

Similarly, the Court has recently shown particular interest in cases that touch on questions of religious liberty. A solidly conservative justice would likely share that interest, and could potentially help solidify a consistent majority favoring a broad understanding of the First Amendment.

While these social issues are being closely watched by advocacy groups, many other legal—and political—questions are at stake in this nomination.

For all his conservative bona fides, Kavanaugh is not necessarily a foot soldier of movement conservatism, according to SCOTUSblog, and his long record of opinions and dissents will offer much grist for confirmation hearings. Soon after the Affordable Care Act was passed in 2010, the D.C. Circuit was asked to weigh in on the law’s individual mandate, which requires Americans to obtain health insurance. The court upheld the law in Seven-Sky v. Holder. While Kavanaugh dissented, he did so in a limited way, writes Jed Shugerman, the Fordham University law professor, on his blog: “Kavanaugh and conservative judges were under enormous political pressure from the right to strike down the ACA,” Shugerman said. “Kavanaugh did not buckle under that pressure.”

In the end, no legal issue is resolved by simple ideological up or down votes. Even big questions can result in small decisions: Take Masterpiece Cakeshop v. Colorado Civil Rights Commission, the recent Kennedy-authored decision in favor of a baker who had refused to make a cake for a gay couple’s wedding. The terms of the ruling were quite specific to the facts of the case, skirting past a core tension between religious freedom and LGBT rights. This kind of ruling can be just as powerful as a broad, sweeping declaration, like the one Kennedy made in Obergefell. Kavanaugh’s voice could be just as powerful in setting limits as it would be in sweeping aside past precedents, as pro-life advocates are hoping on Roe. During his remarks on Monday, Kavanaugh argued for a Supreme Court that rises above politics. “I revere the Constitution,” he said. “I believe that an independent judiciary is the crown jewel of our constitutional republic.”

When the horse-trading politics of Congress meet the Supreme Court, though, it’s easy for those long-term stakes to get lost. Kavanaugh’s celebration may not last long. His path to the Supreme Court is just beginning.

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