how do you distinguish a North Korean made nuclear bomb from one given to them by somebody else?

estimates of DPRK military capability seem based on the number and the quality of nuclear bombs that can credibly be made by their own nuclear program. But, what if some other country decides to give them more or better nuclear bombs while using the indigenous weapons program for plausible deniability? If a few such “laundered” bombs go off, would American or neutral scientists be able to “conclusively prove” that they originated not in DPRK but elsewhere?

Hm, very good question.

I know that the radioactive portions can be fingerprinted as to the makeup of source materials [by the microscopic amounts of different mineral contaminations] so perhaps it could tell if the source of the fissionables was from SovUnion sources, or US sources or Chinese sources.

The “Made in Korea” sticker.

That’s easy: If it works right and can be weaponized, it wasn’t one that North Korea made themselves.

Researchers have recently proved that isotopic analysis gives sufficient clues to ID the source of a nuclear bomb.

Si

Does it matter?
If some other country decides North Korea was responsible for a nuclear bomb, would they bother much about evidence?

The United States invaded Iraq, thought here was no credible evidence that they were behind 9/11.

WWI started after a radical assassinated Archduke Ferdinand. There was no evidence that any of the countries involved plotted that assassination, but that didn’t stop them all from declaring war on each other.

The most obvious way to identify it would be if one didnt go off properly, which would be a serious risk for any nation considering this as a plan.

Far more likely they’d supply plans to make them than an actual weapon, which would be far harder to trace back. They could probably even give the plans for another nations weapons, eg the plans stolen from the US.

Otara

Except for minor details, the ‘plans’ are largely the same in all countries. After all, the principles of nuclear physics work the same in both the US and USSR!

Far harder than getting ‘the plans’ is getting the parts. That’s why a lot of effort is spent in watching the world sales of various components that are needed for nuclear weapons, and trying to prevent them going to states like Iran or North Korea.

There was no evidence because the Serbs didn’t plot with the terrorists. They actively aided them and allowed Serbia to be a base of their operations. That was the issue hand. And it was clear Serbia was allowing this and at the same time it was also clear Austria-Hungary was itching for a fight and had German backing.

FWIW, the book “The Sum of all Fear” dealt with exactly this premise:

Israel “lost” an atom bomb on a strafing run…decades later, terrorists find it, and rework it into a hydrogen bomb, later detonated in Baltimore.

Scientists collecting and analyzing the fallout conclusively prove the fissionable material originated in a particular US facility.

What if it were made in an unknown facility? I can see publicly nuclear countries putting something in the bombs to make them traceable (ie. Apple pie/borscht).

However, what if a secret facility was processing the material? One in which you didn’t know a whole lot about the environmental factors?

-Joe

With the declared nuclear powers, it’s generally pretty simply (well, if you’re a nuclear physicist) to type nuclear weapons. Any country that has ever performed a nuclear test, above ground or even below, can’t avoid dispersing some amount of radioactive material into the air. This stuff is captured and catalogued, and becomes part of a signature for the testing country. This can be augmented at times with on-site collections via treaty monitoring provisions (or hush-hush acquisition). Basically, if it smells like a Russian or Chinese bomb, folks can tell.

The risk, of course, is that there exists these “breakout” facilities that no one knows about. But even then, it’s hard-to-impossible to hide an entire nuclear program. The weapons manufacturing might be hidden, but the reactors enriching the uranium and plutonium might not be entirely off the grid. Sniff some of that material, and you might have enough to recognize the bomb later on.

If the bomb was completely novel, i.e. no one had any idea where it came from, then you’re indeed left with a perfect terrorist weapon, an untraceable nuclear explosion. But the odds of pulling that off are much less than the likelier alternative-- stealing/using foreign material to fake the origin of the bomb, i.e. Al Qaeda detonating a bomb with stolen Russian material, or the aforementioned Sum of All Fears scenario.