That is a known flaw of democracy. The Americans call it the "Vietnam syndrome," where essentially, given the option to exercise their free will, a population will not want war. As you can imagine this is quite an obstacle for the Industrial Military Complex, politicians, central bankers and corporations in general. It was to stop this syndrome that reporters were "embedded" with military watchdogs and coffins could not be photographed. There is a huge propaganda campaign to sell the Iraq war because no one sensible (with proper information) would support it and the hawks know that.
This is a complicated question with no simple solution. I have investigated and found this:
The French revolution, which pretty much began the modern era of the nation state as we know it, never had a chance to realize its revolution fully. Before a truly remarkable system could be set up some elite managed to intervene and sabotage the process. While ideas from Voltaire and other great thinkers were utilized it was done so in a way less sincere than people were lead to believe. Other thinkers like Godwin were pretty much ignored as they advocated so much freedom it, frankly, scared the pants off of the elite. In essence they gave in, so we can enjoy the semblance of freedom we have today, so they could keep their heads, but also to prevent us from getting real freedom. You can get a sense of what I'm talking about from
Howard Zinn, though he takes a very narrow US centric view and is too wrapped up in his own nationalism to see the larger picture IMO.
I think that to change our system would require an immense and difficult campaign to educate people. Few people have any concept of real history and are too frightened for actual freedom. We live with the notion that we need the elite and their system of laws enforced by violence. We see constitutions as granting us freedom instead of the reality which is that they steal it. The vast majority of people think we need the elite and, in point of fact, the elite have gone to great lengths to get us thinking we need them; that an egalitarian system, while nice in concept, could never actually work - or so we are led to think.
Anyway, I could go on but there is really no point. It just pisses people off when I post on this topic because they don't get it. People seem to be genuinely happy with their slavery.