How will we guard/prevent it from being stolen and used in a nuclear bomb
That one we don't have to worry about at least, like I said before, its too low quality for a bomb, and all countries capable of refining it are capable of making the plutonium themselves.....
I beg to differ; some of the isotopes of Plutonium are easily made into a nuclear bomb, and the others that aren't can be made into so-called "dirty bombs". This is a HUGE
problem, especially in the former Soviet republics where radioactive materials are just sitting there with almost nobody looking after them!
Here's some reading to back me up: Plutonium overview