As far as weapons of mass destruction are concerned, think about how difficult it is for one country to trust another. Why should you trust another country? The United States has sent hundreds of thousands of its young men to fight and die in wars throughout its history and has liberated dozens of countries. Many countries in Europe and Asia would not be free today if not for the sacrifice of the United States. Yet the governments from those very same countries often distrust the United States. So how can you expect the U.S. to trust some ruthless dictator with nukes? Not easily.
The only way to get rid of a regime like Saddam’s is through warfare. The liberation of Europe and Asia by the United States and other allied nations in World War 2 cost the lives of many civilians in the very countries they were trying to liberate. But ask people living in France or Belgium or the Netherlands whether they would rather still be under Hitler’s rule in order to spare those civilians. Not likely. And they would have lost even more civilians than that under the rule of a bloody dictator. The same goes for Iraq, if he were still in power Iraq would have lost even more civilians than were killed in the bombings to free the country.
Everyone knows this. However, many countries feel a strong sense of guilt because while countries like the United States and Britain were sending young men into dangerous situations, their own countries sat back and did absolutely nothing. How do you justify this inaction? You must make up excuses. The common one is, “well, the United States bombed Iraq and it killed innocent civilians. You can’t kill innocent civilians, so we had to do nothing.” This ignores the fact that innocent civilians would be dying at an even faster rate in Iraq if Saddam were still there. So the media of these countries show nothing but gruesome images of civilians killed in the bombings, as a way of alleviating their own guilt for allowing these same civilians and more to be killed under Saddam’s rule.
Imagine if the American media did this during World War 2. “We’re sorry, we can’t invade France and drive the Nazis out of there, because some innocent people might die! We’d rather Hitler kill all of the innocent people. Better luck next time.”
Instead, the United States did liberate Europe, and some innocent civilians had to die in order for it to happen. But the world became a much safer place because of it, and most of the world’s countries had to do nothing but sit back and let the Allies take care of it for them. They didn’t have to raise a finger. The only thing they may have needed to do was make a few excuses for their own inaction and treat their guilt over it. 
Fear not, the United States spends millions in research and development of technologies for more and more accurate weapons systems to limit civilian casualties as much as possible. Long gone are the days when a country like the U.S. would need to carpet-bomb the entire city of Baghdad and hope they got some military targets while the whole city was destroyed.
But no matter how good the technology gets, there will always be at least one innocent civilian who is killed in the bombing. And all throughout Europe, that person’s image may be televised to explain to its people “this is why we don’t fight.” In the meantime, their television cameras don’t pan for one second over the mass graves left behind by the dictator.