ON FEB. 21, 1897, this newspaper reviewed the celebrated architect Ernest Flagg’s magnificent Beaux-Arts palazzo on the corner of 17th Street and New York Avenue NW. Created for the newly expanded Corcoran Gallery of Art, the building, according to The Post, belonged to the ranks of “America’s most beautiful structures” as well as those rare constructions “perfectly adapted to the purpose for which it was erected.” One hundred fifteen years later, however, that no longer seems to be the case. The Corcoran’s leadership is no longer sure it can afford the flagship.

As The Post’s David Montgomery and Jacqueline Trescott reported last week, it would cost about $130 million to restore the Corcoran to modern museum standards. The Corcoran College of Art and Design — one of the few of its kind — needs more space, which the current facility, even if renovated, can’t provide. In an ideal world, the gallery and the college would remain in their Washington landmark. But there’s an obvious public interest in expanding an educational institution that cannot at present offer Master of Fine Arts degrees because it lacks the necessary studio space.

Whether or not the Corcoran must sell, there’s also a significant public interest in the building’s future. As David Levy, the Corcoran’s former president and director, recently wrote in The Post, Mr. Flagg’s achievement is “without doubt, the single most important artwork in [the Corcoran’s] collection.” The building, designated a National Historic Landmark, is a paragon of museum design. Should the Corcoran’s trustees decide to sell, they should do everything in their power to find stewards who will honor the building’s history and its potential for showcasing art.

That’s not altogether impossible. The National Gallery, regardless of the results of the push by Rep. John L. Mica (R-Fla.) to expand it into the Federal Trade Commission’s nearby headquarters, could consider the Corcoran as a possible venue for a new wing. Nearby George Washington University, whose studio art students once relied on the Corcoran, could consider merging with the institution, which would bring the university a gallery and art college with international prestige. Or, the Corcoran, with its prime location, could conceivably be sold to the Smithsonian to house a future museum.

In recent decades, the reputation of the District’s first and largest private museum has suffered. The 1989 cancellation of a controversial Robert Mapplethorpe exhibition lost it the respect of many artists; the 2005 failure to secure the necessary funds for a Frank Gehry expansion stunted its advancement. In selling the jewel in the Corcoran’s crown, the museum’s trustees owe it to the city of Washington and to the memory of William Wilson Corcoran himself that one of “America’s most beautiful structures” remains, at his bidding, “dedicated to art.”