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I am NOT mistaken. Apparently you got your information from publicly available information on bomb design as of 60 years ago.

Plutonium and U-235 are both neutron emitters, although at a low level relative to other substances with much shorter half lives. However, each of these can be induced to start a chain reaction simply by putting enough of the material close together.

The problem is how to get enough of it close enough together to explode. Left on its own, it will simply heat up, melt, and self disperse. Any "explosion" will be relatively minor, and result mainly in the dispersal of the radioactive material.

The solution is VERY precise manufacturing, and VERY, VERY precise control of the high explosive (especially the electronic detonators) used to compress the fissile material together. The implosion wave front has to be perfect, which means perfect timing, shape, and placement is mandatory.

Hence the tight controls on international export of the components that are precise enough to be used in this way.

If you can do the above, NO initiator is needed AT ALL. I doubt Iraq, Pakistan, or North Korea could make a reliable small nuke. But Russia certainly can, and so can the U.S.

I should mention that design of very SMALL nuclear weapons requires much HIGHER technology. The reason is that larger weapons have the luxury of over design, including total fissile material well in excess of critical mass. If you use enough excess material, you can make up for a few minor mistakes.

It is also worth mentioning the extra complexity needed for fusion weapons (H bombs), as compared to fission weapons (A bombs). A fusion weapon is vastly more complex, and makes a much bigger bang. The suitcase nukes are fission weapons.

To repeat: NO initiator is needed, AT ALL, for fission weapons if you have precise enough control of the manufacturing. The service life of these weapons is measured in years, based solely on the reliability of the electronic components. The electronics will degrade over time, but the half life of the fissile material is so long that it is simply not an issue.

Since your second response did not contain the flame your first response did, I will simply echo your own words: YOU are mistaken.

Take a look at post #203 and #207, since they aren't from me they may carry more credibility with you.

You made a comment above such that using "excess material" (presumably meaning excess U-235 or Plutonium would make up for poor manufacturing).

That's incorrect.

Placing "excess" fissionable matter in close proximity will result in a merely a radioactive "fizzle".

Moreover, the reason that an initiator/trigger is used is because the critical spherical shape doesn't last very long during the conventional explosive phase. There is a critical moment where the mass is still in the correct configuration, and at that moment the initiator does its deed, but both the gun-type as well as the implosion-type designs fail to maintain their perfect shape for very long during the detonation of whatever conventional explosives are used for the first phase.

Thus, without the preciseness of the initiator, you'll probably just get the above-mentioned fizzle.

Further, it is unquestionable that the material used in the trigger/initiator deteriorates. Radioactive decay is precisely what the trigger requires, but such decay limits the half-life of the isotope.

These triggers have a precise size, shape, and chemical purity that must usually be tailored to a precise core/pit configuration. Thus, replacing a trigger is a non-trivial exercise. Even using a more modern neutron tube trigger requires precise electrical circuits tailored for the type of conventional explosives used, tailored again for the size/shape of the pit/core used (and that is further based upon the chemical purity and size/shape of the fissionable components involved), et al.

The electronics involved also need some very specialized maintenance, as the radiation degrades the circuitry over time.

In short, even if a fully functional weapon (and its arming codes) were GIVEN to Joe Jihadist, he's got a very limited time in which he could detonate it. The longer he waits, the less chance he has that the device will still function.