In message , at 21:17:33 on
Tue, 9 Dec 2008, Recliner remarked:
In the Spooks story, this was an old Russian (pretending to be American)
bomb, placed with a sleeper. And it was in a briefcase, not a suitcase.

I suspect that there's only so far you can miniaturise a nuclear bomb.
You need a certain mass of the fissile material (presumably enriched
uranium), plus various other essential components, including shielding
and conventional explosives.

The "Uranium" part seemed to be inside a stainless steel globe the size
of a tennis ball.

The only thing that may have got smaller in recent years is the
electronics, if any.

And possibly the battery - it seemed fully charged even after being
buried for 20 years.
--
Roland Perry