I think you should re-word your question, just to make it less provocative. Don't get me wrong- I think it is a valid question; I asked a related one myself in an
earlier thread about whether respondents thought that Iran was trying to acquire the bomb (75% of 20 thought "yes").
Here's some points to consider with regard to this question:
1. should any country today, sharing an increasingly smaller planet in terms of how long it takes an ICBM to get from point A to point B, be allowed to develop nuclear weapons? Seems to me we already have enough countries with the bomb and we need to do everything we can to discourage even one more from acquiring them.
2. should we be particularly careful about allowing a non-democratic, politically unstable country with a history of fanatical political and military actions from even pursuing nuclear technology, let alone having even the slightest possibility of developing a nuclear bomb?
3. should we be even more careful when we are dealing with a country ruled by fanatical, religious-based zealots? Zealots that would be quite happy, under the banner of martyrdom, to launch a nuclear weapon first, even if it means their own destruction?
4. should we be suspicious of any country that is developing nuclear power plants, but that refuses to acquire the fuel from a controlled and reliable source? The Russians and maybe even the Canadians would likely be quite willing to provide Iran with nuclear fuel- it there were iron-clad guarantees that the fuel wasn't diverted to weapons manufacture.
5. do you believe that it would be absolutely unacceptable for a country like Iran to acquire nuclear weapons, and that we need to do whatever it takes to stop that from happening? The U.S., Canada, Britain, Israel, Australia, France, Germany, and probably most countries in the world, would agree with this position.
If you answered "no", "yes", "yes", "yes", "yes" to the above, then we really do need to be concerned about Iran, and be willing to use force if necessary to stop the country from acquiring nuclear weapons- but only if diplomacy fails.
If force is necessary, then I think it is of vital importance that countries around the world be united in their efforts to stop Iran, and not let the U.S. and Britain bear the brunt of these containment efforts. Even if cumbersome, I think any response has to come through the United Nations so that the world is seen to be united against a common problem.