Let’s say that Hussein turned out to have something that could be called “unconventional weapons.” So what? 1)Such “unconventional weapons” posed no threat whatsoever to American civilians (even the least apologetic liberal hawks aren’t claiming that Hussein had any ties to anti-American terrorist groups or any independent capacity for deploying weapons abroad). And, even more importantly, 2)the whole “WMD” argument was in itself a massive con. WMD is an umbrella term that conflates the genuinely unique threat of nuclear weapons with many more chemical and biological weapons that don’t have any more destructive capacity than weapons that can be assembled with materials you can purchase at any Home Depot.
The reason the "WMD" argument convinced a lot of people, including myself, is that it was playing off the fear after 9/11. In normal circumstances, during which we weren't just attacked, it would be much harder to convince people that Iraq would use whatever weapons it had against us. Not only that, but if they already had the weapons, why hadn't they been used on us already? That they hadn't refutes the imminent threat argument. If Iraq wanted to use them on us and they really had ties to al Qaeda why not use them when we were attacked on 9/11? Wouldn't that have been the perfect time to get us?
These type of questions weren't asked by enough people because they were under a fog of fear from 9/11, which was being stoked by the Bush administration and the media. If you seriously consider those questions you would see that either they didn't have such weapons or they had little intention of using them against us. Saddam was many horrible things, but it wasn't clear at all that he was suicidal. And that's what you have to be to attack the US with any kind of weapon, especially a nuclear one. You have to wonder with the Bush administration and hawks now and days, whether they would invaded the Soviet Union during the Cold War given what they believe about nuclear weapons. They never explain why mutually assured destruction worked then while it wouldn't now.
Last set of questions. Why, if a country has nukes, would your solution to the problem of them imminently wanting to use them on you be to invade them? If you are right that they have nukes and they want to use them on you, wouldn't attacking them first (with the biggest military in the world by a mile) provoke a counterattack in which they use their nukes? At that point what would they have to lose? Surely Saddam knows that once we invade his fate is sealed. So if he wanted to attack us to begin with it would seem to make a ton of sense that once he thinks his power and life are threatened he wouldn't hesitate to attack us. That's what I would do if I was a horrible dictator.
When you consider all of these questions it's hard to fall back on the "WMD" justification for going to war with Iraq. At worst, if you thought Iraq had nukes, you should have wanted much more diplomacy. Starting a war in order to avoid being attacked by someone who already had the capacity to attack you but hadn't just doesn't make a lot of sense. But fear clouds judgement, which makes for poor decisions. That's not much of an excuse when the stakes are as high as war. But that's the tragedy of reality.