There's something slightly indigestible about the work of post-World War II Japanese photographer Shomei Tomatsu on view at the Corcoran Gallery of Art in "Shomei Tomatsu: Skin of the Nation." Something that sticks in your gut and rumbles long after you've left the museum. Here's a couple of ways the exhibition wall text attempts to put it:

"None of his best photographs simply describes the thing in front of the camera." And "Each is an intricate picture-poem, in which dissonant, even contradictory attitudes contend perpetually with one another."

Let me take a stab at it.

One black-and-white picture appears at first to be of a rustic, hammered-metal bowl, a snapshot of the premodern, "authentically" Japanese culture that the artist is, at least in part, known for. But it's actually a photograph of an upended soldier's helmet, with a piece of skull bone fused to the inside by the heat of an atomic bomb.

Tomatsu is also known for stuff like that: pictures that pack a hidden (and sometimes not so hidden) punch even as they masquerade as prettiness. Pictures of such A-bomb artifacts as a partially melted glass bottle, that is described here, quite accurately, as looking like a "broiled fetus."

But he's also known for shots of beautiful Japanese actresses, beehive-coiffed bar matrons, cherry blossoms, bodies of water, abandoned shoes, U.S. Marines stationed on Okinawa, badly scarred survivors of Nagasaki, blurry overhead airplanes, people looking for work, a man playing cards, kids eating rice.

"The camera," reads one wall panel, "shows the world abundantly while explaining little." That's especially true of Tomatsu's camera, about which one of his early editors at one of the Japanese photo magazines he regularly published in complained that it gave only "impressions."

But what else can photography do? What, other than the skin of things, do photographs ever really show us?

That's what's so hard and slippery about "Skin of the Nation" -- the fact that, on the one hand, it implies that there may be a single "correct" way to "read" that skin, even as it hammers home, again and again, Tomatsu's own ambivalence about what lies beneath it: his love/hate relationship with Americans and the postwar Americanization of his country; the thrill/regret about Japan's subsequent economic boom and the loss of old values; the uneasy emotional space, somewhere between bitterness and affection, that so many of his pictures occupy.

Although the exhibition identifies a central, preeminent theme in Tomatsu's work -- what Japan once was, what it is becoming, and why -- the show has been divided, conceptually if not physically, into 10 overlapping sections: "Apres-Guerre"; "Before"; "The Americans"; "A-Bomb"; "Americanization"; "I Am a King"; "Underground City"; "The South"; "The Post-Postwar"; and "Skin of the Nation." Good luck determining where one section ends and the next one begins, however. Although text panels elucidating each theme appear scattered throughout the galleries, their placement is often only loosely connected to the actual works they describe. The signage discussing a photograph of a group of Marines, for instance, one of whom appears to be shoving his boot into the face of the photographer, hangs nowhere near the actual image.

This, paradoxically, is less a complaint about the show's organization than it is a commentary on the complexity and open-endedness of Tomatsu's work, much of which fits into several thematic categories simultaneously. On the one hand, you could describe his art as being all over the map, addressing at once the subjects of life, death, beauty, ugliness, arrogance and humiliation. On the other hand, it never really strays very far from a single page of the atlas: the complex, inconsistent island nation of Japan and its proud and pain-scarred people.

SHOMEI TOMATSU: SKIN OF THE NATION -- Through Aug. 29 at the Corcoran Gallery of Art, 500 17th St. NW (Metro: Farragut West). 202-639-1700. Open daily (except Tuesdays) 10 to 5; Thursdays to 9. $6.75, seniors $4.75, students and guests of members $3, family groups $12. Children under 12 free. Admission all day Monday and Thursdays after 5 is "pay as you wish."

"Untitled [Iwakuni]," from the series "Chewing Gum and Chocolate," 1960.

"Untitled," from the series "Golden Mushroom," 1990-92.

"Steel Helmet with Skull Bone Fused by Atomic Bomb," 1963.