I wouldn’t worry overmuch about terrorists conducting chemical or biol war.
The way they could carry out chemical warfare is mostly with sabotage at a chemical plant, so if they do background checks, or just not hire Muslims, by (gasp!) profiling, other efforts by them to obtain chemicals will be stopped at point of purchase.
Biol warfare is much, much harder. You not only have to produce a lot of some deadly pathogen, but you have to create a delivery system that is awful hard to fabricate.
The final straw is that terrorists really want big explosions, or at least to kill people face to face. So they don’t put much effort into other means.
“Biol warfare is much, much harder. You not only have to produce a lot of some deadly pathogen, but you have to create a delivery system that is awful hard to fabricate.”
Like the Amerithrax attacks? Or the Rajneeshee bioterror attack in Oregon? Scale either up and you’d have a real problem, plus the fear factor.
Weaponizing the bio agents is the most difficult process. The former USSR had thousands of experts on weaponizing the agents. Where did they all go when the USSR dissolved?