Re: What first amendment?
Too much effort for the same reward as a conventional bomb.
But it's not the same reward as a conventional bomb...
You're thinking like an engineer. You're looking at the actual killing capability of the weapon.
Terrorists don't care about that; they're looking at the amount of fear they can spread among the populace, driven by the number of column inches they get in the press. And a nuclear bomb - however craply implemented - is always going to be the more effective weapon in those terms because the vast bulk of the population has no idea what nuclear weapons really are, and just considers them to be super-scary end-of-the-universe stuff.