Either display or in-text: Caption: Nuclear Weapons: Mk 21 Multiple Independently Targetable Reentry Vehicles of the lgm-118a mx peacekeeper missile Citation: Photo Courtesy of U. S. Army



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Caption: Nuclear Weapons: Mk 21 Multiple Independently Targetable Reentry Vehicles of the LGM-118A MX Peacekeeper missile
Citation: Photo Courtesy of U.S. Army

The Bomb: Nuclear Weapons in the 21st Century
Editor’s Note: This is the first in a series of analyses on the current feasibility and effectiveness of nuclear weapons as an instrument of war in the 21st Century.

Summary


On July 16, 1945, at a remote testing range in southern New Mexico, the United States detonated the world's first atomic bomb. Developing the device was probably the most complex and expensive exercise in applied physics in human history. Even today, weaponizing the atom remains one of the most challenging endeavors a country can engage in -- and one few ultimately choose. Stratfor takes a look at the development of nuclear weapons and at their present-day utility as an instrument of war.

Analysis


The Washington Post reported June 15 that the A.Q. Khan network could have circulated plans for building an effective nuclear warhead, i.e., a nuclear device small enough to be effectively delivered atop a ballistic missile. The possibility that Iran could have received this information makes an understanding of nuclear weaponry -- its historical development and current feasibility -- all the more relevant in a discussion of global geopolitics.
First, two key definitions. Developing a nuclear weapons program [you develop a nuclear weapon, you embark on a nuclear weapons program] is far more complex than simply obtaining a device capable of initiating a nuclear explosion [stick didn’t like the use of ‘bomb’ here, and I tend to agree. Missed it before sending it in for edit, tho], and there is a vast difference between a nuclear device and a nuclear weapon:

  • A nuclear device is simply an apparatus that can initiate an uncontrolled nuclear chain reaction with sufficient fissile material to make a very large hole in the ground. Indeed, both “Little Boy” and “Fat Man” -- the atomic bombs dropped on Hiroshima and Nagasaki, respectively -- were little more than crude nuclear devices, despite the immense complexity of their groundbreaking design and construction. A nuclear device can be as large as a room. The world's first thermonuclear detonation[are you referring here to the Trinity test? No – the “Ivy Mike” shot. Trinity was the first atomic bomb, but thermonuclear is another thing entirely…maybe we should probably say that if it’s confusing: “the forerunner to the first thermonuclear bomb (capable of devastation measured in megatons, rather than the kilotons of early nuclear devices) was achieved…” or some such] was achieved with a device the size of a small building (the so-called “Ivy Mike” apparatus reportedly was referred to as a “thermonuclear installation”). In 2006, the most that North Korea could have tested was a nuclear device, and it may have been something even less. A nuclear device may be “deliverable” in some scenarios, but it is not necessarily of the appropriate scale or robustness to offer a reliable military-strike capability.

  • A nuclear weapon, on the other hand, is a robust, reliable and miniaturized nuclear device (a warhead) that has been combined with similarly robust and reliable delivery system. This synthesis is not to be overlooked. Deliverability is a key feature of a nuclear weapon -- and it must be a practical, militarily efficient means of delivery with a high probability of success, not some fanciful Hollywood vision (e.g., [how do you want to refer to a 24 episode? I’m trying to sidestep the ‘nuclear suitcase bomb’ or a device smuggled in a container ship for now – but will address later]). And the challenges of achieving this synthesis are extensive. For a nuclear device to be deployed as a ballistic missile warhead, as a cruise missile warhead or as a gravity bomb, a series of very significant technical hurdles must be surmounted, including (in addition to nuclear physics), materials science, rocketry, missile guidance and the like.

The delivery of Little Boy and Fat Man, crude devices, was only made possible by the parallel development of the B-29 “Superfortress,” at the time the world's largest and longest-range heavy bomber. It was the B-29 that weaponized Little Boy and Fat Man. Today, modern strategic warheads sit in clusters atop intercontinental ballistic missiles with guidance systems that ensure accuracy within a few hundred yards and fuses that ensure detonation after the extreme stress of launch, the cold vacuum of space and the heat and speed of re-entry.



A nuclear device does not come easy. A nuclear weapon is one of the most advanced syntheses of complex technologies ever achieved by man.

The Beginning

By the end of World War II, the United States' Manhattan Engineering District involved the number of people and the abundance of resources that the American auto industry had at its height in the 19[when? Let’s just say: “of a major industrial sector, amounting to billions of dollars of investment and employing more than 100,000 people” or some such]. The so-called Manhattan Project, [begun in 1942? So named in 1942, yes…and we can say that], was a privileged beneficiary of the country's massive wartime industrial base and drew upon the scientific expertise of the country's -- and the world’s[below we say we are the only country ever to develop a nuclear program independent of other countries; seems slightly inconsistent even with the help of some expats from Europe, they brought raw knowledge of physics, but not experience with an already successful program] -- most esteemed and talented physicists. The entire undertaking was driven by the urgency that can only be applied by a fully mobilized nation engaged in a global two-front war.

And all that effort and urgency almost came too late. By [give me a month and year here by the time Hiroshima and Nagasaki were hit in August 1945], the war in Europe had been won and the Japanese had been beaten back, unbowed, in the Pacific. By this point, the highly enriched uranium sufficiently refined for use in a nuclear weapon was still in such short supply that the relatively simple gun-type design of Little Boy -- used against Hiroshima on August 6 -- was not tested before the bomb was released on the city. (The Trinity device tested on July 16 was of the same more complex implosion design as Fat Man, which was used against Nagasaki three days later.) [Not sure it’s clear here why it almost came too late. The bombs were deployed and used as quickly as possible…they were used essentially as soon as they were assembled and shipped to theater. The Japanese were already talking about surrender and all of the cities of the home islands had been devastated by incendiary bombing…they were done]

Getting There

Ultimately, what made the Manhattan Project unique (aside from its almost limitless resources) was the fact that it succeeding in developing a nuclear weapon[or device? This is a good example of why the “spectrum” analogy I made was useful. Alone, they were just devices, but because of the parallel efforts with the B-29, they were deliverable as weapons – though only just. But I prefer ‘device’ to ‘weapon’] before anyone else did. The basic principle of an uncontrolled nuclear chain reaction was theoretically sound (there was even the short-lived concern that the uncontrolled nuclear chain reaction would spread to the nitrogen in the Earth's atmosphere, with apocalyptic consequences). But because of the complexity of its development, the success of the Trinity device was far from certain. When it proved successful, every subsequent nuclear program in the world could work toward a known goal with increasingly known parameters -- and with increasing help from early adopters.



The French, for example, had limited ties to the original Manhattan Project, while Soviet efforts were propelled by the ruthlessness of Joseph Stalin and a successful espionage program. The Soviets then helped the Chinese (very nearly giving them almost a fully assembled nuclear device) and the North Koreans before eventually cutting off their support. Both China and North Korea were left with substantial foundations on which to build nuclear weapons programs.

The inherent dual-use of civilian nuclear technology for power generation has also proven pivotal at times. Even well-established nuclear powers occasionally shop around for assistance with reactor construction for power generation purposes, and A.Q. Khan's work as a scientist in the Netherlands proved a keystone for a ring[facilitated a number of weaponization programs around the world? Sure…was just trying to follow the wording from G’s diary], from North Africa to East Asia.

Nevertheless, to this day, no country other than the United States has ever independently developed its own nuclear infrastructure and its own nuclear weapon.

The fabrication of fissile material alone -- the one true limiting factor in the development of a nuclear device -- presents significant challenges. The concept of separating a heavier isotope [of uranium? yes] from a lighter isotope of uranium in order to enrich the stock to higher than 80 percent U235 -- sufficient for use in weapons -- is well understood. In practice, the quality of equipment must be extremely high to ensure such high levels of separation when differentiations of only atomic mass are involved.[don’t quite get this. seems vague and unclear; can we be more descriptive and specific? Separating something heavier from something lighter in a gaseous state is not all that hard – either technically or conceptually. But doing it on a sufficiently refined level to separate two isotopes differentiated by only a few subatomic particles is extremely difficult] [The alternative,? sure] reprocessing[fabricating? No…plutonium is created inside a reactor but it then must be separated – reprocessed is the appropriate term – from the reactor output…trying to keep this readable and not go all P4 on the readers, so lemme know what you think] plutonium, is chemically obtainable[what does this mean? It is a chemical process and not nearly as challenging as enrichment] but extremely nasty[how so? Toxic, radioactive, requiring it to be done remotely], and plutonium can be fabricated only inside an operational nuclear reactor.
Suffice it to say that, in practice, neither way of fabricating fissile material is simple. While Iran is currently enriching uranium in centrifuges, it is not clear that they[who/what? centrifuges] are anywhere near sufficient quality to actually achieve high levels of enrichment. And despite a concerted national effort, the Iranians seem to be struggling to bring a meaningful number of centrifuges online.

Compared to the challenges of enrichment, the fabrication of a simple gun-type device like Little Boy is comparatively simple, though precise and extensive calculations[and equipment? Nope, just calculations and some decent machine tools…Little Boy was essentially a short artillery tube] are still required. But only uranium can be used in a gun-type device; plutonium requires the far more complex method of implosion, which presents numerous challenges, including the precise “lensing” of high-grade explosives. The purity of the lenses, their arrangement and the timing of the detonation must all be carefully crafted and coordinated to create a perfectly symmetrical explosion that compresses the plutonium core to a supercritical mass. Again, theoretically, it is a fairly understandable concept. In practice, however, it requires a great of knowledge and expertise. The creation of even the most primitive implosion device during the Manhattan Project challenged the best scientific minds and technology available at the time.

Taken as a whole[do you mean fabricating fissile material and developing either a gun-type device or an implosion device? Yes – essentially everything we’ve discussed above], this is a path that only eight or nine countries in the world have successfully travelled. Of those countries, South Africa has since renounced [and dismantled it’s weapons? yes] its program while North Korea may or may not have a working device.[Can we name the other countries? They’re all in Stringer’s graphic]

Weaponization

To move beyond the device stage toward weaponization, numerous other technological barriers come into play.

First, delivery systems must be devised and both the bomb design and the payload capacity for the delivery system appropriately tailored. The delivery system itself -- whether air-drop, cruise missile or ballistic missile -- involves significant technological challenges, including aircraft design, subsystems integration and the development of complex guidance and propulsion systems. Indeed, these remain developmental challenges for many established nuclear powers. Ballistic missile design is an especially complex undertaking -- to say nothing of mating such missiles with a submarine for undersea launch.

In each case, the physics package (the components of the bomb that actually initiate a nuclear explosion) must be significantly miniaturized to one degree or another. A modern re-entry vehicle is a steep conical shape shorter than a human being that contains an even smaller physics package weighing only a few hundred pounds. Getting a warhead down to this size is no easy task.[this is a general statement we’ve already made. we need to elaborate here with specifics. what are some of the challenges? You’re starting to get very far into the realm of extremely classified...I’d say exceptional precision manufacturing, exceptional quality control and extensive experimentation. Your understanding of the dynamics of boosted fission and thermonuclear explosions must be exceptionally precise…you’re talking about having supercomputers to run computations on…]

Then there are the decades of testing and practice necessary to ensure detonation upon delivery, national command authority controls and the like. Indeed, U.S. National Labs[is this the formal name of one lab or a general reference to many such labs in the U.S.? there are about four “National Laboratories” that serve the nuclear weapons enterprise] still use some of the world's most powerful supercomputers to model the effects of age on the current U.S. nuclear arsenal.

Developing a nuclear weapon is not simply a matter of money, resources and brains. It also is the product of decades of testing (now frowned upon by the world community), design experience, numerous fielded weapons and a sustained annual investment of billions of dollars.


An aspiring nuclear power today does not have such options. The frantic pace of the Cold War arms race is over, nuclear testing is almost universally banned and the costs imposed by the international community [such as? Sanctions, ostricization (look at DPRK)] are higher than the costs of developing and maintaining a program. Thus, the calculus to proceed with such an endeavor has proved to be a discouraging one for most countries. Only Pakistan and possibly North Korea have joined the club since the fall of the Berlin Wall in 1989.



Next: Are Nuclear Weapons Relevant Anymore?

RELATED LINKS


www.stratfor.com/analysis/russia_sustaining_strategic_deterrent
www.stratfor.com/analysis/china_challenges_defensive_nuclear_arsenal
http://www.stratfor.com/themes/military
http://www.stratfor.com/theme/ballistic_missile_defense


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