Members of the US government have openly talked about using tactical nuclear weapons against Iran.

I think it's pretty ridiculous to suggest that Hezbollah would use nuclear weapons against Israel if they had them. They're too physically close to Israel for that. They would destroy themselves in the process. The fact that you can't see this, quite frankly, scares me quite a lot, since you have said that you are a 'rocket scientist' and you allude to being involved in fairly sensitive kinds of programs.

Iran is not using nuclear blackmail. They have repeatedly said that they do not intend to develop nuclear weapons, and that their nuclear program is for energy purposes. They are entirely within their legal rights to have such a program according to the Nuclear Non-proliferation Treaty.