Switzerland's nuclear program stayed one step away from actually putting together a nuclear weapon for several decades straight. The fact that they could become a nuclear power, but haven't, and could credibly restart their program if attacked, is of strategic importance to them.
Is it building towards a bomb if your intention is to sit on the precipice of building a nuclear weapon for the rest of time, leveraging your position as deterrence, but never going over the edge? I have no idea! I also have no idea whether this describes Iran. Saying that there's "no question" they were building towards a bomb is ignoring this question, though.