[Stefan Stackhouse]

Of course, it decays out into Helium-3, which is a neutron sink...which is why you have to swap it out every few weeks. Doesn't take much He3 to poison a chain reaction, or so I am led to believe.

Not so frequently as every few weeks, but every few years, yes. Half life is around 10 years or so. I don't believe that they don't need to recharge the SLBMs while they are at sea for months at a time, for example.

If the story implies that these were obtained by OBL no later than 1998, then they might possibly need a recharge by now. My guess is that they had not been recharged for many years when OBL bought them -- those who sold them to him knew that they would be duds. If OBL has procured some relatively fresh tritium within the past 2-3 years, we are in deep danger.

[WyldKard]

Not so frequently as every few weeks, but every few years, yes. Half life is around 10 years or so. I don't believe that they don't need to recharge the SLBMs while they are at sea for months at a time, for example.

What I was always lead to believe was that while you could get away with years on a large warhead, or hydrogen bomb (seven years or so.) It was closer to weeks for a suitcase nuke because there are such small sizes involved...that the He3 produced in just a few weeks worth of decay is enough to risk compromising the chain reaction. Of course, I could be wrong, too...

[steve-b]

I don't believe that they don't need to recharge the SLBMs while they are at sea for months at a time, for example.

SLBMs can carry larger warheads, which don't need as much (or perhaps any -- I don't know the details beyond what is obvious to anyone familiar with nuclear physics, and wouldn't say if I did) tritium kick-starting.