That's a great point. I didn't take into account the legal consideration of intent. https://www.law.cornell.edu/wex/intent https://www.law.cornell.edu/wex/inte

That's a great point. I didn't take into account the legal consideration of intent. https://www.law.cornell.edu/wex/intent https://www.law.cornell.edu/wex/intent So, I guess if the FBI knew hypothetical pipe bomber was around, they would arrest him. If it was the FBI, and they were looking for him specifically, they would most likely have sufficient additional evidence to prove intent. This is because he would have had to get on their radar somehow, and however that happened would likely supply sufficient evidence to prove intent. Local police would have to take a different approach, since they would have a much more difficult time proving intent. If they just arrested some random guy with tannerite and a pipe, the prosecutor would then have to go out and construct a case for intent from scratch.