WASHINGTON – The Supreme Court ruled Thursday that a gigantic Latin cross on government land in Bladensburg, Maryland, does not have to be moved or altered in the name of church-state separation.

The justices reasoned that the 40-foot cross was erected nearly a century ago as a World War I memorial, not an endorsement of Christianity. Although their verdict could extend to other existing monuments, it does not offer a blank check to new ones.

The opinion by Associate Justice Samuel Alito concluded that the display does not violate the Constitution's establishment clause because of its longevity and multiple messages. The vote was 7-2; Associate Justices Ruth Bader Ginsburg and Sonia Sotomayor dissented.

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"The cross is undoubtedly a Christian symbol, but that fact should not blind us to everything else that the Bladensburg Cross has come to represent," Alito said. "A government that roams the land, tearing down monuments with religious symbolism and scrubbing away any reference to the divine, will strike many as aggressively hostile to religion."

The ruling protects what Alito called similar "ceremonial, celebratory or commemorative" monuments.

"Where monuments, symbols, and practices with a longstanding history follow in the tradition of the First Congress in respecting and tolerating different views, endeavoring to achieve inclusivity and nondiscrimination, and recognizing the important role religion plays in the lives of many Americans, they are likewise constitutional," he said.

Ginsburg dissented from the bench and in writing. "Just as a Star of David is not suitable to honor Christians who died serving their country, so a cross is not suitable to honor those of other faiths who died defending their nation," she wrote.

It was another in a series of high court decisions defending religious freedom, from allowing public prayer and allocating public funds to exempting religious objectors from laws regarding contraception and same-sex marriage.

Many justices, many opinions

The question before the court was simple: Does the 93-year-old "Peace Cross" violate the First Amendment, which prohibits government establishment of religion?

Even if the answer was yes, few of the justices who heard the case in February wanted to see it moved, altered or demolished. Conceived in 1919 by bereaved mothers of the fallen and completed by the American Legion six years later, the war memorial has become part of the town's landscape.

A federal district court judge ruled in 2015 that the monument did not violate the Constitution's ban on government establishment of religion. In 2017, a federal appeals court panel reversed that decision, calling the cross the "preeminent symbol of Christianity."

Even if that's so, Alito ruled, crosses are commonplace as grave markers. "If you look today online at pictures of American cemeteries in Europe, what would strike you is this row after row of plain white crosses,” he said from the bench.

Ginsburg disputed that rationale for maintaining the cross, which she said "is a common marker for the graves of Christian soldiers precisely because it symbolizes the foundational tenets of Christianity."

Other justices wrote separately to justify other reasons for allowing the cross to stand. Associate Justice Clarence Thomas called it "clearly constitutional" despite any and all religious connotations. Associate Justice Brett Kavanaugh said it should survive based on "history, tradition and precedent." Associate Justice Neil Gorsuch said challengers did not even have legal standing to sue.

By contrast, Associate Justice Stephen Breyer said the cross essentially was being grandfathered in, but "a newer memorial, erected under different circumstances, would not necessarily be permissible."

Justice Department spokeswoman Kelly Laco heralded the court's ruling as "a win for protecting religious freedom and American historical tradition."

Some defenders of religious liberty said the ruling did not go far enough.

"This decision leaves in place the tangled confusion of past Establishment Clause opinions, which are currently being used to remove religious messages, signs and symbols from public squares around our country," said Travis Weber, vice president for policy at the conservative Family Research Council. "These issues will continue to arise."

Complicated case history

Part of the problem is the high court's own convoluted case history: a series of rulings on the intersection of government and religion that some justices acknowledged left the rules in disarray.

For nearly a half-century, the court's seminal doctrine has been the "Lemon test," named after the decision in 1971 that was intended to define what government could and could not do when it comes to religion. But over the years, the justices have ignored the very rules that lower courts continue to follow.

In 1971, the court said any government role must have a secular purpose, cannot favor or inhibit religion and cannot excessively entangle church and state. Years later, it outsourced part of the decision-making process to a "reasonable observer."

In 2005, the justices created exceptions to their original test for passive religious displays, such as Nativity scenes or the Ten Commandments. In a case upholding legislative prayer in 2014, they incorporated history and tradition into the mix.

At the Supreme Court, the Trump administration joined dozens of religious, municipal and veterans groups defending the memorial. They argued that the court's mixed messages on religious liberty had forced legal battles to be decided "display by display.”

Waiting in the wings are state and local governments across the country that have their own monuments to worry about. The Veterans of Foreign Wars and municipal groups warned that hundreds could be affected, from the steel beams that form the Ground Zero cross in New York City to a memorial in Taos, New Mexico, that commemorates the Bataan Death March.

Two of the most prominent displays rise above Arlington National Cemetery: the 13-foot Argonne Cross, erected in 1923 and dedicated to "our men in France," and the 24-foot Canadian Cross of Sacrifice, donated in 1927 to honor U.S. citizens who served abroad in the Canadian army.

A group of 30 states led by West Virginia listed dozens of war monuments large and small that could be challenged if the Supreme Court ruled against the Peace Cross, from Gettysburg National Military Park in Pennsylvania and Georgia's Chickamauga Battlefield to La Mesa, California, and Coos Bay, Oregon.

The American Humanist Association, which brought the challenge to the Maryland cross, disputed those numbers. The group won a federal appeals court ruling last summer that threatens a 34-foot cross towering over a city park in Pensacola, Florida, but it said few other displays are in jeopardy.