Suitcase nuclear device

A suitcase nuclear device (also suitcase bomb, backpack nuke, mini-nuke and pocket nuke) is a tactical nuclear weapon which uses, or is portable enough that it could use, a suitcase as its delivery method. Thus far, only the United States and the Soviet Union/Russian Federation are known to have possessed nuclear weapons programs developed and funded well enough to manufacture miniaturized nuclear weapons. Both the United States and the Soviet Union have acknowledged producing nuclear weapons small enough to be carried in specially-designed backpacks during the Cold War, but neither have ever made public the existence or development of weapons small enough to fit into a normal-sized suitcase or briefcase. It has also been reported that Israel has produced nuclear warheads small enough to fit into a suitcase.

Overview
The Center for Defense Information (CDI) claims that a detailed training replica—with dummy explosives and no fissionable material—was routinely concealed inside a briefcase and hand-carried on domestic airline flights in the early 1980s.

While the explosive power of the W54—up to an equivalent of 6 kiloton of TNT (though the more common yield was much lower)—is not much by the normal standards of a nuclear weapon (the bombs dropped on Hiroshima and Nagasaki at the end of World War II were around 16 to 21 kilotons each), their value lies in their ability to be easily smuggled across borders, transported by means widely available, and placed as close to the target as possible.

Similar-sized weapons
In nuclear weapon design, there is a trade-off in small weapons designs between weight and compact size. Extremely small (as small as 5 in diameter and 24.4 in long) linear implosion type weapons, which might conceivably fit in a large briefcase or typical suitcase, have been tested, but the lightest of those are nearly 100 lb and had a maximum yield of only 0.19 kiloton. The largest yield of a relatively compact linear implosion device was under 2 kilotons for the cancelled (or never deployed, but apparently tested) US W82-1 artillery shell design, with yield under 2 kilotons for a 95 lb artillery shell 6.1 in in diameter and 34 in long.

Russian
The highest-ranking GRU defector Stanislav Lunev claimed that such Russian-made devices do exist and described them in more detail. These devices, "identified as RA-115s (or RA-115-01s for submersible weapons)" weigh from fifty to sixty pounds. They can last for many years if wired to an electric source. In case there is a loss of power, there is a battery backup. If the battery runs low, the weapon has a transmitter that sends a coded message—either by satellite or directly to a GRU post at a Russian embassy or consulate.” According to Lunev, the number of "missing" nuclear devices (as found by General Lebed) "is almost identical to the number of strategic targets upon which those bombs would be used."

Lunev suggested that suitcase nukes might be already deployed by the GRU operatives on US soil to assassinate US leaders in the event of war. He alleged that arms caches were hidden by the KGB in many countries for the planned terrorism acts. They were booby-trapped with "Lightning" explosive devices. One such cache, identified by Vasili Mitrokhin, exploded when Swiss authorities sprayed it with a high pressure water gun in a wooded area near Bern. Several others caches were removed successfully. Lunev said that he had personally looked for hiding places for weapons caches in the Shenandoah Valley area and that "it is surprisingly easy to smuggle nuclear weapons into the US" either across the Mexican border or using a small transport missile that can slip undetected when launched from a Russian airplane. US Congressman Curt Weldon supported claims by Lunev but noted that Lunev had "exaggerated things" according to the FBI. Searches of the areas identified by Lunev have been conducted, "but law-enforcement officials have never found such weapons caches, with or without portable nuclear weapons."

United States
The lightest nuclear warhead ever acknowledged to have been manufactured by the U.S. is the W54, which was used in both the Davy Crockett 120 mm recoilless rifle–launched warhead, and the backpack-carried version called the Mk-54 SADM (Special Atomic Demolition Munition). The bare warhead package was an 11 in by 16 in (28 cm by 41 cm) cylinder that weighed 51 lbs (23 kg). It was, however, small enough to fit in a footlocker-sized container.

Former Under-Secretary of Defense for Intelligence Michael Vickers has claimed that he, along with other Green Beret special forces troops, practiced infiltrating Warsaw pact countries with backpack-sized nuclear weapons, with a mission to "detonate a portable nuclear bomb."

In 1994 the United States Congress passed The National Defense Authorization Act for Fiscal Year 1994, preventing the government from developing nuclear weapons with a yield of less than 5 kilotons, thereby making the official development of these weapons in the U.S. unlawful. This law was, however, repealed in the National Defense Authorization Act for Fiscal Year 2004.

Works
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