by Sam Kean
CHAPTER 34
Alsos
After fleeing Denmark, Niels Bohr sailed to the United States to advise on the Manhattan Project, and he proved just as much of a security nightmare in America as he had in Europe. He first visited New York, a dangerous city for an oblivious jaywalker like him; more than once he almost got creamed crossing the street. Then, on a cross-country train ride to New Mexico, he kept blowing his cover by forgetting his code name (Nicholas Baker), and an armed guard had to sleep outside his room at night to keep him from wandering off. Worst of all, he blabbed about fission research to anyone who’d listen. Things got so bad that General Leslie Groves had to drop everything he was doing to join Bohr for the last leg of the trip, which he spent lecturing the physicist—“for twelve straight hours,” Groves recalled—about the need for discretion. Bohr instantly saw the wisdom in this and promised not to say another unauthorized word to anyone. He even succeeded in keeping his vow for a good five minutes after arriving in Los Alamos. But as soon as Bohr saw his old colleagues, at a reception in his honor, he started babbling again—spilling every secret Groves had just warned him to keep mum about. The man was simply incapable of keeping his trap shut.
Although the Great Dane proved a valuable mentor at Los Alamos—at fifty-nine, he was the eldest scientist at the lab, thirty years older than the average—the immediate result of his trip was to heighten the paranoia about the Nazi atomic bomb, especially for Groves. Groves was not a hysterical man by nature, but as one of his staff noted, “He worried the hell out of the German bomb project during the war.” Bohr’s account of his conversation with Heisenberg in 1941 only deepened the general’s unease. He also rehashed the Heisenberg Sturm und Drang for Oppenheimer and other top officials at Los Alamos; this included pulling out the sketch Heisenberg had made, which caused quite a stir. To be sure, everyone concluded that it looked more like a nuclear reactor than a bomb, but the sketch was two years old at that point; Germany had no doubt made great progress since. And if nothing else, you could use reactors to breed plutonium.
Or worse. In addition to plutonium, running a reactor created all sorts of nasty by-products that were ideal for so-called dirty bombs. Although dirty bombs also require radioactive material, they differ from fission bombs in important ways. Fission bombs kill by releasing gobs of energy all at once; they vaporize you. Dirty bombs kill by releasing deadly isotopes that wriggle inside your body; they poison you. And while fission bombs require a nuclear explosion, dirty bombs don’t. You simply have to spread the dirty radioactive material around, which you can do with regular explosives; you can even mix the material with smoke or powder and use crop dusters to spray it on troops or cities.
As of 1943 there was no hard evidence that Germany was making dirty bombs, but the very idea of them contaminated the minds of Manhattan Project scientists, filling them with lurid visions. In the summer of 1943, project officials installed secret nuclear-defense systems in Boston, Chicago, New York, San Francisco, and Washington, with Geiger counters wired to air-raid sirens in case of attack with radioactive species. There was talk of preemptive strikes as well. Enrico Fermi pulled Robert Oppenheimer aside one day and suggested manufacturing deadly strontium-90 to poison food and water supplies in Germany. Oppenheimer met this horrifying suggestion with enthusiasm, and abandoned it only after determining that they probably couldn’t kill enough people to make it worthwhile. He wanted at least half a million dead Germans, or why bother?
The paranoia reached its peak, or nadir, in late 1943. Based on projections about the rate of German research, several scientists convinced themselves that the Nazis probably had enough radioactive material by then to make several dirty bombs. Nazi propaganda minister Joseph Goebbels then ratcheted up the tension by declaring that Germany would soon unleash a revolutionary “uranium torpedo” on the Allies. The only question was when, and for various reasons American fears began to coalesce around dates in December. For one thing, security always slackened during the holiday season. For another, Hitler clearly loved stagecraft and grand gestures—witness the Berlin Olympics and his storm troopers goose-stepping through Paris. He would certainly plan the attack to maximize its emotional impact. And what day could be more devastating than Christmas or New Year’s Eve? Their imaginations now at full gallop, a few American nuclear scientists actually sent their families to hideouts in the countryside in late December to protect them. They then endured a grim holiday week alone by the phone, their stomachs churning with acid, awaiting news of the atomic apocalypse.
Nothing like that happened, obviously, but the hysteria once again highlighted the fact that Manhattan Project leaders had no idea what German scientists were really up to. At the time, the United States had pathetic intelligence capabilities, and there were no espionage units with scientific expertise, which meant they were probably overlooking vital clues. (The vast majority of people, for example, still considered uranium a useless metal.) And the problem would only get worse over the next year. By late 1943 the Allies had gained footholds in Italy and were planning to attack occupied France in 1944. Every newly conquered city meant new chances to gain precious atomic intelligence—or alternatively, to let it slip away.
To fix this problem, one of Groves’s deputies came up with a plan. Rather than rely on third-hand rumors from abroad, he decided the Manhattan Project should build its own intelligence unit to scour Europe. It would consist of both scientists and soldiers, and they would spend their days infiltrating labs, deciphering secret documents, and interrogating captured scientists. This was something new in the history of warfare: no one had ever turned scientists loose like this on an espionage spree. The team would report directly to Groves and would operate in strict secrecy, allowing no one in the field to know what they were searching for. The closer they could get to the front lines, the better.
The program became known as the Alsos mission, a name based on a multilingual pun: means “grove” in Greek. But when the object of the pun, Groves himself, discovered this Easter egg, he was furious. He didn’t find it cute, and furthermore considered it a security hazard, since anyone who knew his role on the Manhattan Project could then infer what this scientific outfit was doing in Europe. (There’s evidence, in fact, that a few British agents did deduce the purpose of Alsos based solely on the name.) No one in Groves’s office ever confessed to this etymological crime, and by the time Groves found out about it, the name had already started circulating within the Pentagon. Changing it would only draw more attention, so he grudgingly let it stand.
Groves eventually widened the scope of Alsos beyond nuclear science, figuring that as long as people were ransacking German labs, they might as well learn all they could about radar, rockets, jet engines, and biological weapons, too. But in large part, these other topics served as a beard, a way to obscure the mission’s real goal: hunting down secrets about the Nazi nuclear bomb. Alsos also had the authority to seize atomic matériel like uranium and heavy water, and even scientists themselves. As the mission evolved, in fact, manhunts became its top priority. All the uranium on earth wouldn’t do much good without a Hahn or a Heisenberg to sculpt it into weapons.
Given their hostility to Groves, the British hated Alsos. The existing intelligence apparatus worked just fine, they insisted; there was no need to deploy a bunch of skittish scientists to the front, especially when they ran a high risk of being captured and interrogated, no doubt “in the Russian manner.” Groves cared not a whit for what the British thought, but he shared their concern on this last point. Therefore none of the scientists who worked on the Manhattan Project were eligible for Alsos—they simply knew too many secrets.
Ruling out everyone on the Manhattan Project, however, left very few candidates for the role of chief scientific officer on Alsos. Ideally, Groves wanted a nuclear physicist with some experience studying neutrons and cyclotrons. He couldn’t be a theoretical egghead, though: the job would be as much detective work as anything. Given the dangers involved
, he would have to be pretty eager to do something for the war effort, and knowledge of Europe and its languages would be a nice bonus. But where on earth would they find somebody like that?
Luckily, the selection of chief military officer went more smoothly. Groves already had a candidate in mind, in fact, a former science teacher with experience in irregular warfare—someone just as obsessed as he was with security and someone who needed to get transferred out of his current post before he enraged every general in the army. Boris Theodore Pash.
PART V
1944
CHAPTER 35
Busy Lizzie
Despite the raid on Peenemünde, the British continued to tremble over the German V-rockets: they remained a “crossbow,” as one official put it, “aimed at England’s heart.” The situation looked menacing enough by February 1944 that Winston Churchill felt compelled to warn the House of Commons about the huge concrete bunkers in northern France. The Reich had forty thousand workers toiling away there by that point, and the sites were expanding at an incredible clip: some contained more concrete than Hoover Dam. Pouring so much money and matériel into unproven weapons was a big risk, especially given how strapped the German economy was, but as one historian noted, “The Führer always brightened when mention was made of some wild and grandiose scheme. If it involved the use of hundreds of thousands of tons of reinforced concrete, he was ecstatic.” By that criterion, no scheme in the Reich could have made him happier than the ominous bunkers.
Especially because one of the bunkers, at Mimoyecques, would house Hitler’s beloved V-3—officially named the Hochdruckpumpe (high-pressure pump) but informally dubbed the Busy Lizzie. According to the first sketchy reports the Allies received, the V-3 would stretch twice as long as the V-2, measuring an incredible 92 feet, with a 118-foot wingspan. It reportedly weighed 40,000 pounds, half of that explosives, and could reach speeds of 435 miles per hour. The most fantastical spec was its range, more than 6,000 miles. Which meant, forget London—Busy Lizzie could smite New York and Washington.
(Attacking the United States might sound absurdly ambitious for Germany, but it was one of Hitler’s fondest dreams during the war, and his henchmen developed several schemes to do so. The loopiest was probably Projekt Huckepack, the Piggyback Project. It called for filling a bomber to the snout with fuel and pushing it as far over the Atlantic Ocean as it could go and still make it back to Germany. Right before it turned around, a slender, pencil-shaped plane would detach from its belly and continue on. If everything went right, this piggyback plane could just reach Manhattan and unload its bombs. Afterward it would splash down at a rendezvous point in the ocean, where a submarine would surface and pick up the crew. Now, the pencil bomber would have limited firepower, perhaps only a few bombs, which hardly makes the effort seem worthwhile—unless those bombs were unimaginably powerful. As powerful as, say, nuclear bombs. And there are hints that the Nazis considered such a tactic, turning Germany’s Manhattan Project against Manhattan itself. Even if it carried conventional bombs, one successful piggyback strike would force the United States to divert soldiers and sailors to its coastline rather than shipping them to Europe. Moreover, as al-Qaeda proved decades later, striking New York would have provided the Reich with an immense psychological boost.)
Perhaps not surprisingly, the rumors about the incredible size of the V-3 turned out to be just that—not credible. In truth the V-3 rockets measured less than a tenth of their reported 92 feet, and their range fell far short of 6,000 miles. V-3s weren’t even real rockets, since they couldn’t launch on their own. But that didn’t mean the V-3 wasn’t scary—there’s a reason Hitler relished it. The Busy Lizzie was essentially a 416-foot rifle that shot nine-foot bullets. The difference was that, instead of using one explosion to propel a bullet, the way a normal rifle does, Lizzie used several precisely timed explosions along the length of the barrel to accelerate the bullet in stages, pumping it to near-supersonic speeds. And while a single nine-foot bullet obviously wouldn’t do as much damage as a V-1 or V-2, Lizzie made up for her lack of punch with an incredible rate of fire: the Nazis planned to operate twenty-five pump guns near Mimoyecques, which would allow them to shoot a round every six seconds. That would mean up to 14,400 V-3s crashing down on London every day. As Goebbels said, “Twice as many inhabitants are crammed into London as Berlin. For three and a half years they have had no sirens. Imagine the terrific awakening that’s coming!”
Now, a 416-foot gun sitting out in the open would of course have been an irresistible target for bombers; it wouldn’t have lasted even an afternoon. So to protect Lizzie, some five thousand German engineers started digging. They opened huge tunnels in the limestone hills outside of Mimoyecques, and anchored the rifle barrels in the bedrock thirty-five stories beneath the surface. (Anchoring the barrels like that also helped absorb the unfathomable recoil.) Because the guns loaded from the breech (the back end), the engineers also had to dig access tunnels for the nine-foot bullets. For additional protection, the openings of the muzzles at the surface were surrounded by eighteen-foot-thick domes of concrete and covered (when not in use) with eight-inch-thick steel plates, which were camouflaged with haystacks.
To be frank, the Busy Lizzie was a long shot. Accelerating a bullet that size with a series of explosives would have required ridiculously precise timing, probably beyond the reach of electronics back then. In fact, at the V-3 proving grounds west of Berlin, test after test failed in the spring of 1944, with the bullets either exploding inside the barrels or tumbling out of control during flight. Given all this, several historians dispute that the V-3 ever could have worked. That said, Albert Speer—by far the most sober and realistic Nazi in Hitler’s circle—swore that end-stage tests were on the right track. And modified V-3s were successfully fired against troops in Belgium and Luxembourg later in the war.
Regardless of the V-3’s actual potential, what mattered at the time was that Nazi leaders believed it would work—as did the Allies. The danger seemed especially acute given the existence of a German nuclear weapon program. No firm evidence ever linked Mimoyecques with Vemork or the Uranium Club, but there were always allusions, whispers, and once people started associating the two in their minds, the idea continued to fester. After all, what other weapon could justify so much money, so much labor, so much concrete? It had to be nukes. One Manhattan Project physicist was so scared of atomic rockets that he started listening to the BBC broadcast twice every day—not for the news, but to reassure himself that London still existed. Even General Dwight D. Eisenhower, the supreme Allied commander in Europe, could only shake his head when briefed on the sites and mutter, “You scare the hell out of me.”
Clearly, the Allies needed to neutralize this threat—and quickly, before the Germans reinforced the bunkers beyond the point that bombing them would do any good. Eisenhower therefore decided that strikes against rocket sites, including the bunkers, would receive the highest priority of any mission in Europe aside from the D-Day invasion. The U.S. army and navy accordingly got to work, and developed a scheme so outlandish it would have made the kooks in the OSS smile. The navy arm was called Operation Anvil, and Joe Kennedy was one of its first volunteers.
CHAPTER 36
Groves’s Second Assault
In early 1944, General Leslie Groves went on the offensive again, albeit in an unorthodox way. Rather than bomb only military and industrial sites, he decided that the time had come to take out scientific targets. His primary goal was to evict researchers from their “comfortable” labs and delay their work, but he certainly wouldn’t oppose more permanent measures. As one report put it, “the killing of scientific personnel… would be particularly advantageous.”
After fielding suggestions from Manhattan Project leaders, Groves focused the strikes on the cherry tree–lined streets of Dahlem, a suburb of Berlin where Otto Hahn and Werner Heisenberg worked. Because no one had ever bombed a laboratory before, the area was virtually defenseless on the evening of February
15, 1944, when a squadron of planes swooped in and unloaded. Both labs suffered heavy damage, especially Hahn’s nuclear chemistry institute; one bomb landed more or less in his desk chair and blew out the entire southern wall of his office. The building’s rafters soon caught fire, and the surviving scientists tried to salvage books and equipment by passing them hand to hand in a chain. They then stepped back and watched the roof blaze red against the nighttime sky—a “terrible-beautiful sight,” one recalled.
By lucky coincidence, Hahn was absent from Berlin at the time. He was in fact scouting around for new lab space in the Black Forest region of southern Germany, to put himself beyond the reach of raids like this. The trip no doubt saved his life. Still, the sixty-four-year-old chemist lost most of his life’s work to the bombs; he especially bemoaned the destruction of personal letters from scientists like Ernest Rutherford.
The Dahlem strike had secondary effects as well. On the German side, it hastened the evacuation of Uranium Club members to the Black Forest. On the Allied side, it made German scientists seem like legitimate targets for attack, and in doing so helped revive another unorthodox plot. Way back in 1942, two of Samuel Goudsmit’s friends had drunkenly proposed kidnapping Werner Heisenberg in Zurich. They’d passed the idea to Robert Oppenheimer, who in turn alerted his superiors, but as far as Goudsmit knew, the higher-ups had dismissed the idea. In reality, Oppenheimer was still chewing it over, and had even expanded its scope: because if snatching one German scientist was good, snatching several German scientists was better. To help military folks identify them, Oppenheimer began compiling dossiers on seven German nuclear scientists. And as the idea was bandied about at meetings in Los Alamos, someone there (Groves never revealed who) finally cut to the chase and said, If you’re so worried about enemy scientists, why not just rub them out?