@cjd

So the only party who *could* be theoretically interested in chemical of bio warfare, or dirty bombs, are terrorists because as the story goes they are just crazy and don't care for life.

But they don't and never did, except for one attack with sarin by Japanese sect Aum Shinrikyo. There can be many reasons for that but in general terrorists do have clear friend-or-foe definition so an indiscriminate weapon with "global* potential isn't an option as it would hit their friends.