The Smithsonian Institution has built us a new American Indian museum and is developing an African American one. "Retratos: 2,000 Years of Latin American Portraits" -- which opened yesterday in the Smithsonian's International Gallery on, or more precisely, underneath the Mall -- furthers the agenda.

"Retratos" is the Smithsonian's latest exercise in what might be called identity aesthetics. It's a serious effort.

Four curators; three organizing museums (the National Portrait Gallery, the San Antonio Museum of Art, El Museo del Barrio of New York); five venues; and 115 objects borrowed from 76 collections in 15 countries.

The result is a real treat to see.

It's not its arguments that make it so. It's its objects.

Yes, pre-conquest South America had extraordinary portraitists; yes, the baroque opulence of the Counter-Reformation Roman Catholic Church shaped the look of painting in the colonies; yes, the region's artists took many cues from Europe, and still do so today. These points are worth making. But all might have been argued with objects worse than these.

What these portraits share is not just their Latin Americanism but also their quality, which is high. Of the 1,200 likenesses considered for inclusion, fewer than 10 percent got in.

Portraits are an acquired taste. It's nice if they're excellently painted, but it isn't enough. Whom they're pictures of also is important. The portraits one remembers most seem to be inhabited. There's a person in them, and a time.

"Retratos" begins with a sort of a prefix, a set of Moche ceramics, pots with faces, made nearly 2,000 years ago in what is now Peru. They're not generic; they introduce specific individuals. This one has a scarred lip, that one is half-blind. They seize your full attention. They look you in the eye.

That jolt of encounter is common in "Retratos." If you were doing such a show you'd want the first known portrait painted in the New World ("The Mulattoes of Esmeraldas," 1599, from the Prado in Madrid), and Jose Gil de Castro's "Simon Bolivar" from 1830, and you'd want superb examples of the elaborately crowned nuns who were so often portrayed in rich Viceregal Mexico. You'd also want some startling corpse paintings. And all these things are here.

To satisfy the public's hunger for celebrity, you'd have to have a knockout Frida Kahlo, and a portrait by Diego Rivera (who was twice her husband) that is strong enough to hang by it. These pictures are here, too.

The most startling corpse portrait on view is that of a baby boy who died in 1805; he's covered in pearls and diamonds, and he also has wings. The 1830 Bolivar, a propaganda piece of liberator-as-hero, has in the decades since spawned a thousand like it. The Kahlo is, of course, a picture of herself, one that calls attention yet again to her small moustache, her one continuous eyebrow, and her fascination with herself. The 1913 Rivera, a cubist work, shows how much that Mexican nationalist imported from abroad.

Many of the pictures in "Retratos" have never before been seen in the United States. The curators responsible -- Marion Oettinger of San Antonio, Fatima Brecht of New York, and Carolyn Kinder Carr and Miguel Bretos of the National Portrait Gallery -- have hung a distinguished show.

Such displays do not come cheap.

Ford Motor Co. donated more than $2 million -- for research, travel, tour expenses, a Web site, a 300-page catalogue and a lot of educational programs. The Smithsonian's Center for Latino Initiatives gave $110,500 more.

Twenty-four U.S. senators, 79 representatives, dozens of Maryland legislators, the governor of New York, the mayors of Miami, San Diego, Baltimore and the District, have lent their names to "Retratos' " "Committees of Honor."

Big lumbering committees don't do much for art shows. Nor do politicians with diversity agendas.

Latino initiatives, like this one, have an honorable purpose -- to assuage perceived injustice, and celebrate a people who have not always had their due. Some part of their spirit is egalitarian and inclusionary and anti-elitist. But such initiatives are tricky. Especially when they're art shows. Art shows, if they're any good, have to be exclusionary. They can't help it. Some paintings are a lot better than others. These are. They declare their superiority the moment that you see them. They belong to the elite.

Retratos: 2,000 Years of Latin American Portraits, in the International Gallery of the S. Dillon Ripley Center, 1100 Jefferson Dr. SW, through Jan. 8. The gallery is entered through the pavilion just east of the Smithsonian Castle. Hours are daily from 10 a.m. to 5:30 p.m. Admission is free. For more information see www.si.edu/ripley

Frida Kahlo's "Self-Portrait With Thorn Necklace and Hummingbird," 1940."Retratos: 2,000 Years of Latin American Portraits" captures strong, memorable images. Left, an elaborate 1805 Mexican corpse portrait of a baby boy, "El Nino Jose Manuel de Cervantes y Velasco," adorns the child with angel's wings and covers him in pearls and diamonds. Above, a Moche artist created this stirrup spout portrait vessel, painted and slipped earthenware, between A.D. 100 and 800.