Pretty difficult, actually. NAZI Germany tried to build nukes and failed, as did WW2 Japan. The Soviet Union had to steal the secrets to the bomb from turncoat Americans (Rosenberg's). France and England had to get it from us. China got it from the Soviet Union and gave it to Pakistan. India developed their nukes independently, as did the coalition of Israel, South Africa, and Taiwan.
Refining U235 is a nasty process, and getting Plutonium requires a breeder reactor. Then once you've got it, you still need to know how to work on a metal (Uranium and Plutonium are metals) that is extraordinarily brittle and hot, yet needs to be machined to tolerances more demanding than aircraft parts. How many nations on this planet can even manufacture mere aircraft parts? Not many.
Then once you've got all of that figured out, you've got to have electronics that can withstand intense radiation, and in at least one case, must be extraordinarily well-timed.
Then you have to figure out how to deliver it without dying of radiation sickness (and your delivery vehicle has to have electronics and components that aren't overly impacted by whatever radiation leaks from your "bomb".
Oh, and you have a fixed amount of time to use it, 'les the natural decay (read: half-life) of the uranium, tritium, or plutonium reduces the fissionable mass below the critical mass level, rendering what was once a nuke into a mere dirty bomb (i.e. worthless for everything except creating panic in uninformed societies).
Then again, maybe you don't have to figure that bit out.
Half life is of no consequence for uranium and plutonium. Tritium is another story -- If H-bombs exist without a plutonium trigger, as I've heard, they would truely be of the use it or loose it variety.
But a dirty bomb set off in a large city would be a major disaster.
I personally think that Islam has killed itself on 9-11. The more people examine it the stupider it looks. The more terrorist acts, the more people will examine it.
Not true. Israel worked with the French, who agreed to pool nuclear research with them after the Suez crisis, when they were "dropped" by Eisenhower's threat to withdraw the US nuclear umbrella (leaving them vunerable to the Russians, who duly rattled sabers their way), after their joint move against Egypt.
And the French did not simply get it from us or the Brits. They had a long research project, with testing in the western Sahara and later in the south Pacific, De Gaulle's insistence on an independent nuclear deterent ("force de frappe"), etc. Israeli scientists worked in French labs and shared in the results.
France and India are the two confirmed cases of independent success, not simply based on prior espionage. It should also be said, however, that the tech for it and knowledge of the engineering difficulties involved have become more widespread over time.
For what it is worth...
I seem to recall the Brits were involved in the Manhattan project, notably Geoffrey Taylor & James Tuck. Don't know enough about the French to say how they got there.
That having been said, the precision required to build a nuke is overstated, especially when producing early designs (assuming that Iraq didn't get "bogus" designs). Of course, those designs needed to be carried on the largest bombers of the day (B-29s and B-36s), so you won't see them flying on SCUDs. Indeed, depending on the design chosen by Iraq, the timing issue is moot (again, that particular family of designs precludes both missile/artillery launches and very high yields). If, however, Iraq wanted nuke missiles/artillery, they would have to have access to advanced designs and precision.
Electronics, also, is highly fungible. Outside of the timing issue (only an issue with certain designs), the electronics used need not be overly-advanced. Iraq would not need nearly the same level of weapons safety that the rest of the nuclear world takes for granted, as even an accidental, premature detonation would fulfil Saddam's purposes. Morever, Saddam's not going to sit around for 42 years and watch his country literally fall apart without lashing out at least once with his nukes.
Along the lines of safety, the poor sod that's asked to deliver an Iraqi nuke and become an instant martyr for the Iraqi Islamist cause will NOT be making it back. As long as (a) he doesn't croak of radiation poisoning before he reaches his target and (b) his plane (could also be a ship; in fact if the target were US soil, it would almost have to be a ship) doesn't drop out of the sky due to radiation-induced metal fatigue, no one will care that he took enough rads to kill him inside of 2 weeks on the way to the target.
Building # 100,001 is much easier than building #1.
Then once you've got it, you still need to know how to work on a metal (Uranium and Plutonium are metals) that is extraordinarily brittle and hot, yet needs to be machined to tolerances more demanding than aircraft parts. How many nations on this planet can even manufacture mere aircraft parts? Not many.
Actually most aircraft parts have extremely sloppy tolerances. I know first hand that Cessnas will happily chug along with ice or goose sized holes on the wings. Unless you mean the tolerances for jet engine parts. Mass producing is hard, yes, but any decent physics grad. student can do .0005" without much trouble. Furthermore, I wouldn't be surprised if pre-machined parts are on the market. Everything else is in Moscow. I saw CD ROM's of the Moscow police databases for sale on the street. Officier's names, home addresses, case info.
Refining U235 is a nasty process, and getting Plutonium requires a breeder reactor. Then once you've got it, you still need to know how to work on a metal (Uranium and Plutonium are metals) that is extraordinarily brittle and hot, yet needs to be machined to tolerances more demanding than aircraft parts. How many nations on this planet can even manufacture mere aircraft parts? Not many.
Why refine? Russia and Central Asia are awash in these materials.
Then once you've got all of that figured out, you've got to have electronics that can withstand intense radiation, and in at least one case, must be extraordinarily well-timed.
Either half of Iraq has kidney stones or they have been buying medical equipment to scavenge electronics for a plutonium implosion device. A U-235 gun requires no electronics at all. You could build one that employed a flint-lock if you had a perverse sense of techno-irony.
Oh, and you have a fixed amount of time to use it, 'les the natural decay (read: half-life) of the uranium, tritium, or plutonium reduces the fissionable mass below the critical mass level,
Obviously you overengineer for a long shelf life. Bio's are obviously readily available (ask the anthrax mailer) and can be employed without the restraint the mystery man mailer has exhibited.
Would we not then act premptively?
I doubt there's much beyond their capacity except the acquisition of purified uranium235 or plutonium. The rest is complicated engineering and electronics, but not anything we can count on being beyond their ken.
It's unlikely Iraq could build a thermonuclear bomb in the foreseeable future, but the older, uranium type is awful enough.
There was on one of the UNSCOM reports a mention of a model bomb, or prototype, without of course the active ingredent. The indication was that its predecessor had been tested at least for the basics. Whether the test was really a useful one or not is another matter, it may have been a political show to make Saddam think his scientits were making progress so he wouldn't get angry. It could have been something which would fail and be at most a dirty bomb.
But now that you pointed that tolerance in manufacturing out, I reckon if they have to order aluminum pipes they are trying to make up for a weakness in their system; the inability to accurately produce even custom tubing for the centrifuge/refining process. I think one of the most difficult tasks on the design of the Blackbird was the landing gear. The aircraft heated up so much in flight that they had to find a solution to prevent the tires melting and parts failing because of the effects of extreme heat. Tolerances and material properties become a big issue under those circumstances, so must be more so when dealing with the something like this kind of bomb.
I was interested in how secure already refined material is in the former USSR. How bulky and heavy would a smaller crude weapon be with shielding be? I've heard that if such a thing is under water it is harder to detect, but how far under wouid it have to be to shield it from detection? And if it were placed in the bottom of the hold of an oil tanker, immersed in crude, would that be a waste of time to prevent detection?
I suppose it does look more like it's just an extra-intense Baker-type warning to the Iraqi elite. Even Scott Ritter's message to the Iraqi congress seemed to be a made-to-order warning to get the ultimatum through to the next group down from Hussein in Iraqi authority, the people most likely to be able to deal with him. Maybe Ritter was at least useful in getting that message across when broadcasting it might not do the trick, even if it was his real intent or not.