[drdaeman]

But is chemistry illegal? I think anyone can have all the equations they want to have (like, idk, U238 -> Th234 + alpha particle) - just can't possess some actual substances (Uranium). So I don't think the comparison is valid.

[Eisenstein]

That's exactly the point I was making. It seems I did a poor job -- it is impossible to make chemistry illegal but it is possible to regulate possession of some chemicals.