July 14, 2004

Suitcase Nukes
Posted by Dale Franks

I am going to have to respectfully disagree, in part, at least, with my colleague, McQ, on the seriousness of the issue of portable, or "suitcase" nukes.

First, it is certainly possible to build such a device. The smallest nuclear device ever created by the US, was the W-54 warhead, which was created for use in the Davy Crockett nuclkear bazooka. There was also a backpack version of this device, the Mk 54 SADM. This warhead weighed 51lbs, or 23kg. This was a 1-kiloton warhead, which compared to the 13kt Hiroshima bomb, makes it pretty weak in nuclear terms.

As to whether the Sovs ever built such a suitcase nuke device specifically, well, that's hard to say. The Center for Non-proliferation Studies has looked at the possibility, and finds it's difficult to say if such devices even existed.

The report points out that there are indications that Spetsnaz troops were assigned to plant nuclear mines in case of invasion. But, with a suspected weight of 90KG (198 lbs) that CNS identifies, you'd need a pretty big frickin' suitcase.

For the most part, the worry about Soviet-era suitcase nukes seems to have come from one intervies of General Alexander Lebed conducted in 1997, where he made reference to them. Before that time, references to them were almost non-existent, as have references to them from Russian sources since then. At the time, though, the statements touched off a firestorm in Russia, but with inconclusive results. As CNS concludes, practically every participant, from Gen. Lebed to Minatom officials had perfectly good reasons to hide the truth, whatever it might have been.

We do know, though, that the Sovs did have nuclear 152mm howitzer shells that weighed around 30kg (66 lbs) but they were a) small-yield (from 0.1 to less than 1 kt), and b) required regular and frequent routine maintenance to remain operational. Moreover, the indications were that these shells were maintained in a less than fully assembled state, in order to maintain positive control over them, with rapid assembly to take place in case of war.

Very short maintenance cycles would, in any event, be required to keep such a device operational. While it is possible to produce a 10kt yield with a fairly light device i.e. slightly less than 100kg (220 lbs), using a minimum of plutonium to achieve critical mass, the device would require the use of tritium to increase the yield. Without proper and regular maintenance, the yield would within a couple of years, decline to minimal levels as the tritium degraded.

Finally, there is the issue of positive control mechanisms (PCM). The soviets were quite keen on separating the authorization to use nuclear weapons from the physical possession of them. In general, the KGB controlled the launch codes with the Armed forces controlled the weapons. Anyone in possession of a weapon, who could sell it off to a terrorist group or rogue state, would not be in possession of the PCM that made the weapon operational. That would render the weapon useless for ordinary purposes.

So, to sum up:

1. It is possible the Sovs produced some miniature devices, though the evidence they did so is sketchy.

2. The devices would probably be a bit big for suitcases, weighing in at around 80-120kg.

3. The devices would require frequent routine maintenance, or would become inoperational.

4. The positive control mechanisms usually present in nuclear weapons would prevent their use as designed, and would be practically impossible to circumvent.

What remains then is the possibility of extracting the nucelar materials for use in a radiological device, or "dirty bomb" by terrorists, or for rogue states to extract the processed nuclear material for use in a nuclear weapon of their own design.

So, I am not particularly worried about the possibility of a bunch of suitcase nukes going off in the near future. This doesn't mean the government should ignore the threat, but there's no reason to be exceptionally worried about the possibility.

REBUTTAL: (McQ) And with equal respect I'm going to have to offer a bit of a rebuttal to my esteemed colleague, Dale (we sound like a couple of UN ambassadors for heaven sake).

"Suitcase nuke" is simply a euphemism for a relatively small and portable nuclear device. There's no requirement that it actually fit in a suitcase. As Dale notes, the US has a whole family of "suitcase nukes" which are officially known as Atomic Demolition Munitions. In fact, this link shows pictures of such US devices.

Please note in the first picture that the total weight of the entire device is less than 400 lbs with a yield up to 15 kilotons. Also note that its not much bigger than a can of fountain syrup used in a fast food resturaunt. Certainly nothing that would be that difficult to move around or disguise.

So obviously there's no question the technology does exist to have devices larger than 1kt in a relatively small package.

As to the problem of maintenance, the IPCS piece I cited points out that the program for bin Laden is being run by "a Western educated Arab nuclear scientist, (turned Islamic Jehadi) and assisted by five Turkoman Muslim. Others too have been brought from CAR countries." In other words they hired in the maintenance help.

Obviously because of the maintenance requirement, their contingent would have to be larger than the first six mentioned but that has to be assumed to have been covered by the fact that IPCS notes "others" were brought in later. There's also a discussion of Pakistani help at other sources which I'll try to run down again.

The problem of PCM is also addressed in the piece:

To overcome the technical problems of coded transmissions for activation of these nuclear suitcase bombs (Russian technique,) it is reported that Laden’s nuclear experts could “hot-wire” them and these can be used by human-bomb volunteers from amongst the Islamic Jehadis seeking martyrdom.

I'm not an expert in these things but I have enough experience to know that there's usually a work-around to just about everything. The fact that the PCM is mentioned as well as an implied work-around ("hot-wire") infers the problem was recognized and addressed.

As to the genesis of the reports, it appears the Center for Nonproliferation Studies may have some conflicting "conclusions". Drs. Scott Parrish and John Lepingwell agree that Lebed's testimony wasn't fully convincing, but they also note that the government denials became "increasingly self-contradictory and less credible."

Pertaining to Lebed and the government of Russia, Parrish and Lepingwell note:

It certainly does indeed stand to reason that if we had them, they'd have them as well. Anyone at all familiar with that era know the USSR developed many copies of US and Western weapons and weapons systems. Getting the goods on a 10 to 15kt ADM isn't at all beyond their capability. And its further not beyond reason to conclude that they might have significantly improved on something first built in the '70s by the '90s.

Parrish/Lepingwell conclude:

Lebed's charges have therefore not been adequately dismissed by his critics, nor fully substantiated by his supporters. The claims that the Soviet Union never built ADMs ring hollow, but neither is there any solid evidence indicating the loss or diversion of such weapons. This does not mean that the threat of diversion does not exist, though. The social, political, and economic stresses that wrack Russia provide strong incentives for military "insiders" to steal nuclear weapons.

Again, if one reviews the history of the collapse of the USSR its not at all a stretch to make the case that nukes could have been diverted for economic reasons (some scientists weren't paid for 2 plus years) as well as emerging religious reasons (especially among the newly minted muslim states where these "buys" by OBL are alleged to have taken place).

One other bit of information which really seems to throw more weight to the argument that some nuclear devices could have been lost than to the side which says they're all accounted for comes from Dr. Alexie Yablokov (Boris Yeltsin's former science advisor)in a 1997 interview:

During beginning of '70s, in USSR have been made some number -- nobody knows exactly -- some number of small- sized suitcase-size nuclear munitions. For what? For terroristic [purposes]. Exactly; only for terroristic [purposes].

So here we have the admission that in the '70s ADMs were made, but they don't know how many. How's that for nuclear accountability?

I would speculate that its also probable that except for a few, no one knew how long the program continued nor how it evolved. And just because the US discontinued its ADM program years ago does not mean the USSR did so as well.

It seems, then, rather improbable that a resonable claim can be made that a) all nuclear devices are accounted for and b) that the USSR's ADMs were only small yield devices. According to Yablokov's statement, there would be no way to corroborate either claim.

So while I think Dale makes some good and cogent points, I don't share his relative lack of concern about the possibility of nuclear attack by terrorists using small portable nuclear devices. I don't think anyone would argue that the administration was worried about ICBMs falling into terrorist hands.

There are too many loose ends in the former USSR, many brought about by the secrecy endemic to a totalitarian regime, to have me not believe, in this particular case, that where there's smoke there may be fire. Money talks and BS walks and when OBL was hunting nukes, money was talking very loudly in the former USSR.


I have some problem with the idea that the nuclear experts could have 1) performed the required maintenance, or 2) could simply have "hot-wired" the PCM.

The maintenance were are talking about isn't quite as simple as checking to see that all the electrical connections are working. There is the matter of replacing the tritium, which would require a fairly sophisticated engineering setup to replace the yield-boosting mechanism, as well as having access to the appropriately refined tritium on a regular basis. Those are not inconsequential hurdles.

As far as PCM goes, having worked nuclear security for a couple of years, I don't think hot-wiring will do the trick. Each nuclear device is equipped with what the US calls Permissive Action Links (PALs) that prevent the device from unauthorized arming or detonation. In general, the PALs consist of electronic devices that not only require an authorization code, but the code must be appropriately encrypted. For weapons manufactured after the 1970s, they generally require that the code be transmitted from a centralized, remote location, preventing local troops from arming them. In addition, PALs are generally buried deep within the warhead, to prevent hotwiring without disassembling the weapon.

"Hot-Wiring" the PAL means completely disassembling the weapon, replacing the PAL with a rather tediously manufactured non-cryptographic, electromechanical replacement. It's not a simple matter of simply "cutting the blue wire".

This would require a facility of some degree of sohistication that includes radiation isolation, and waldo remotes to perform the actual operation. Such facilities are hard to find anywhere in the Arab world. Indeed, the technology to even build them would have to come from outside the region.

And this facility would need to be available on at least a quarterly basis for the regular replacement of at least the tritium yield-increasing modules, as well as the other components on some less frequent, but necessary basis as well.

I just don't think this could be done without state sponsorship. It's not just the requirement to have nuclear scientists (whatever that means), but a rather sophiticated manufacturing/maintenance infrastructire that cannot be built ad-hoc, but that requires sophisticated equipment and facilities generally unavailable anywhere in the Mideast, outside government facilities.

I just think that the article glosses over the technical hurdles to modifying such weapons, without direct state sponsorship.

LAST POINT FOR McQ Dale makes good points as usual. However, I'd simply point to the possibility of such state sponsorship being no further away than Iran, a state we know precious little about except a) its engaged in a nuclear program of its own (so the facilites and technical expertice certainly exist) and b) is known to sponsor terrorists.


Ah, ha ha, but now we're talking about something other than a terrorist attack. Now we're talking about an overt act of war, by one state sponsoring a nuclear attack on the soil of another. We've stepped outside the terrorist sphere, and are back in the sphere of hot state-on-state action.



I thing if they had nukes, there would already be a smoking crater in Isreal somewhere. Then they would say they have more and blackmail the West into their demands.

Posted by: Wayne Fiebick at July 15, 2004 10:34 AM

OBL either has nuclear scientists on his side, or he doesn't. If he does, then could they work over a used, under-maintained suitcase nuke and make it into something unpleasant? If he does not, then perhaps OBL purchased the suitcase nukes not knowing they were no longer operational?

Posted by: Wacky Hermit at July 15, 2004 10:53 AM

Wayne made the same point I was going to make: if Al Qaeda had ever gotten their filthy hands on something like a "suitcase nuke" they would have used it already. If you're an evil terrorist and you come into possession of a nuclear weapon, why would you take the risk of sitting on it, and being captured by any one of the dozens of intel/law enforcement agencies that are constantly scouring the ends of the earth to capture you? Not to mention the maintainance problems Dale pointed out, which for a sophisticated, miniaturized weapon like a "suitcase nuke," would almost certainly be beyond the capabilities of even a state sponsor like Iran, let alone a group of free-lance scientists operating covertly with a terrorist organization.


Posted by: bob at July 15, 2004 03:19 PM

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