@fatboy; i'll repond by number.
1&2)Well it is not legal as put forward by Aether. There are more UN resolutions supporting the NNPT. Morally it is up to my morals isn't it. The question I put to myself is, what are the risks. I think that if Iran has nukes, the chance that nukes will be used in the world increases (i sort of argued that before). There are enough nukes around the world to ensure mutual fear, so that is no reason why Iran should have nukes. The actual morals behind that are using nukes is bad and having a nation with too much power in the world is bad. The rest is more practical.

3) I am sure that europe would rather not, because of, as you said, who you are actually hurting and also because a boycot hurts on both sides (more on Irans side ofcourse). But the problem is that nukes are very, very dangerous, they kill by the millions. So what leverage does europe have. A boycot of Iran is not the goal. So maybe boycot for a short while, just to show europe is not kidding. Then lift them at the first excuse.

4) All depends on the situation. The actual danger (not created fear) presented by Iran. Invasion with the UN (or some huge coalition) probably, without almost certainly not.

5) I imagine you noticed the sarcasm. Well again all depends on the situation, not on the time it takes to find a solution. I can imagine a situation where i would be grateful for a US invasion, like a day before the nukes are actually flying. On the other hand i would like to think that the world can arrange it's problems (if necessary with a widely supported invasion) without one nation deciding what is right for everyone, based on shameless manipulation of facts and public opinion. The latter is pretty insulting in my opinion.

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