On the surface, a boiling cloud of radioactive water and steam penetrated the surviving ships. Radioactive material adhered to wooden decks, paint, rust and grease. For weeks after the tests, the Navy tried to wash off the fallout with water and lye, sending crews aboard the contaminated ships to scrub off paint, rust and scale with long-handled brushes, holystones and any other “available means.” In August, worried about radiation, Admiral Blandy cancelled plans for a third test and gave orders to sink badly damaged ships. As Operation Crossroads steamed away from Bikini, it towed the battered, irradiated fleet of targets to nearby Kwajalein, and then to Pearl Harbor, Bremerton in Washington, and Hunter’s Point and Mare Island in California. There, sailors stripped the hulks of ammunition and left them to rust.

Starting in 1948, the Navy began taking the Crossroads target ships to sea and sinking them. The explanation was that the sinkings were part of training exercises and tests of new weapons. That year, Dr. David Bradley, M.D., a radiological safety monitor at Bikini, published his journal of the tests in a book titled No Place to Hide. It stayed on the New York Times best-seller list for ten weeks. No Place to Hide was a forceful book that told the “real” message of Bikini. According to Bradley, Operation Crossroads, “hastily planned and hastily carried out… may have only sketched in gross outlines… the real problem; nevertheless, these outlines show pretty clearly the shadow of the colossus which looms behind tomorrow.” Bradley’s metaphor was the target ships rusting at Kwajalein, many of them seemingly undamaged but “nevertheless dying of a malignant disease for which there is no help.”

The “cure,” being enacted as Bradley’s book was printed, was to sink the contaminated ships. In February 1949, Washington Post columnist Drew Pearson called the tests a “major naval disaster.” He reported that “of the 73 ships involved in the Bikini tests, more than 61 were sunk or destroyed. This is an enormous loss from only two bombs.” Pearson, like Bradley, pointed to what he viewed as a military effort to keep the true lesson of Operation Crossroads — the virtual destruction of the target fleet by radioactivity — from being fully apprehended by the public. Although the story had ultimately leaked out, it was downplayed by the government, and the credibility and patriotism of those who spoke out was questioned.

I traveled to Bikini as part of Dan Lenihan’s National Park Service team in 1989 and 1990. Lenihan, Larry Nordby, Larry Murphy, Jerry Livingston and I were the first to visit most of the wrecks since Operation Crossroads, and we were undertaking the survey at the request of the U.S. Department of Energy and the Bikini Council. The Bikinians, in their exile on the remote island of Kili, far away from their contaminated homeland, were eager to work with the Department of Energy to see if the sunken “swords” could be transformed into tourism plowshares. The National Park Service had the government’s only team of diving archeologists at the time, and our park-oriented approach was not at odds with tourism. Since I was the NPS maritime historian, I easily wrangled my way onto Dan’s crew. As well, my proximity to the National Archives and my love of research meant that I could do advance work to learn about the history of the ships and the tests, and thus help the team to figure out just what we would be seeing in the blue depths of Bikini lagoon.

In 1989 the U.S. Navy did a magnificent job of surveying the lagoon’s 180-foot depths to relocate the sunken ships of 1946. There was no chart documenting the location of the wrecks, so the Navy started with nothing but the generally known location of the aircraft carrier USS Saratoga, whose mast rose to within 50 feet of the surface and whose grave is marked by oil leaking from its fuel tanks. Our first dive at Bikini was on Saratoga.

Anchored over the wreck of USS Saratoga, we bob in the slight swell as each diver checks his gear under the blazing hot sun. Rolling backward into the water is a welcome relief. Clustered together like a group of skydivers, we fall in unison onto Saratoga. The carrier is huge, its 900-foot length the largest thing I have yet seen underwater. The superstructure towers above the flight deck, and in the clear water, it feels as if we are flying down the side of a tall building. Open hatches and deadlights invite inspection, but for now, we focus on the gaping maw on the hangar deck. Landing on the flight deck, we pause, and then one by one, drop down farther into the hangar. The flight elevator, bent and collapsed, lies at the bottom of the huge shaft. I turn left and head into the dark cavern of the hangar, following Dan and Murphy’s lights.

Lying on the deck is a rack of 500-pound bombs. Wedged beneath their noses is a smaller depth bomb. I suck in a little more air and, inflating my lungs, float just a little higher to avoid going near them. The deck below me is covered with silt, and I try not to stir it up. In the distance, I notice that Dan and Murphy’s lights have stopped moving. As I swim up, I see why. They have halted at a plane. Sitting upright on its wheels, wings folded up for storage, is a Helldiver, a dive bomber introduced late in the war. The cockpit is open and the gauges on the pilot’s panel are clearly visible. The plane is ready to roll out onto the elevator, rise to the flight deck and be readied for combat. If that is not exciting enough, there are two more intact planes in a row behind the Helldiver. Saratoga carried planes on the deck and in the hangar when the atomic blast sank her on July 25, 1946. Since the flight deck above us is largely empty, the survival of these planes in the hangar is something we had not envisioned. Rather, we had figured that being picked up and flung across the water by a nuclear tidal wave had smashed everything inside Saratoga. Not so, and as if to underscore this fact, Dan floats up to a row of unbroken light fixtures.

We move on to a hole punched through the flight deck. Rising up through the hole, we pass scattered equipment lying on the deck and look for the lines dangling from our dive boat. We hang there, above the wreck, decompressing to quiet down the gas in our blood and prevent the bends. We are many miles away from a decompression chamber, so we’re being careful to avoid a dive accident that could cripple or kill us. Bikini is a challenging dive location, to be sure. There are the unexploded bombs, and the fear of residual radiation. And there are the risks of entering rusting hulks that might collapse on us. In addition, the ships are artificial reefs that attract hundreds of potentially aggressive white tip sharks. Then there’s the greatest danger, the depth. The wrecks lie on the bottom of a 180-foot-deep lagoon, with the shallowest depth at Saratoga’s multistory hull as it rises up from the seabed. These are beyond the limits for most divers, particularly when using regular air and not a mixed gas. In 1989–90, our team breathes regular air, all that is available at our remote location, and we decompress with pure oxygen to scrub our blood clear of the nitrogen bubbles that build up on long dives.

Thankfully, no one gets the bends, though we have a few close calls. One dive team member runs out of air and nearly panics until another diver assists with a spare regulator from his tank. A few days later, I carelessly go too far, fascinated by a deck full of test equipment, and turn back dangerously low on air. I make it back to the decompression line with an empty tank and the reminder that as fascinating as wrecks are, you can’t appreciate them when you’re dead.