If it had come to a large scale confrontation with the Soviets, don't be so certain nuclear weapons would have been ruled out. After all, they were the reason we managed to stockpile so many in the first place, and vice versa. We have been at the brink of nuclear war in the past, even after modern warfare conventions had been agreed upon.
Never in a million years do I want you to think that I enjoy war, or that the loss of human life is to be taken lightly just because I support the use of force with Iraq. These difficult decisions are based on what threats the future holds. The idea is to prevent a greater amount of deaths down the road. The world will be better off without Saddam in it. Given free reign, do you really think that he would not develop nuclear weapons and not hesitate to use them when he had the chance (either in the Mid-East or elsewhere)? If just one nuclear weapon were to be detonated in a populated area, it would geometrically outnumber the amount of lives lost in the last conflict with Iraq and however many future battles with them may produce. What do you think the world would be like, if he say, had a hundred. The chemical weapons he produces and stockpiles will also more likely bring death to his own people faster than another conflict will. With no restrictions on Saddam, Iraq would become even more of a terrorist conduit, where known terror organizations are aided, with Iraq maintaining deniability, and making his mass destruction weapons available. If we do not finish this situation, once and for all, it sends Iraq the message that they have won, and greenlights their covert weapon production.
It seems to me that you approach this situation from the viewpoint of 'why don't we just live and let live?' And that isn't such a bad thing. Iraq, however, has never and will never see it that way. One simply cannot sit by idle, while people of this nature are allowed to develop a first-strike offense, because once they have it, they will use it.