"The world is a hell-hole of war and murder, so lets go ahead and make more war?"
No, but let's not pretend that we live in a fantasy world, in which world problems are solved by ivory tower "experts".

"For tens of thousands of years, the only way we had of governing ourselves was the BigMan of some form or other- chief, dictator, king, emperor. Then some folks, bit by bit and generation by generation, took a stand and democracy and the notion of the individual came into being. Should we never have questioned the rule of kings because no examples of something else existed?"

This is an over simplification of last 10,000 years. First, most of this 10,000 years we are lacking information as to how various governments of the world were organized. Second, your term "BigMan" is vague, but one could say that this "Bigman" type of governing hasn't changed. The aspect which is changing is ever increasing creation and distribution of knowledge. Such concepts as Rule of Law, balancing power, and rights of citizens, have evolved, though they are not new- though it's unlikely they were at any time as articulated and sophisticated as in modern time.

"For tens of thousands of years all we had was belief and superstitions, and most explanations of the way the universe operated hinged upon some notion of deity. Then some folks, bit by bit and generation by generation, thought their way out of the demon haunted world. Should we never have questioned the way we thought as 'human nature' ? "

UFOs, GM food, Global Warming- we haven't escaped the 'demon haunted' world. Besides, no one has ruled out demons- science's focus is on what can be proven, to focus on what is self evident by repeatable experiment. Demons & etc are simply put in a bin which is labelled "not something which is knowable at this time by the scientific method".

"Maybe war is human nature, but we will never know until we try something else. War has only 'worked' maybe a few times in all of recorded history as a way of bringing about affirmative, positive change (WWII is just about the only one I can think of, going all the way back as far as I have read history). I say we try something else and demonnstrate our merit as a species."

War is a few humans who get together who will do anything in order to get what they want. War is human nature as much as talking is human nature and changing the environment/reality is human nature. Probably the most well known war which brought about "affirmative & positive change" was the American War of Independance. Of course, one shouldn't over look the costly but significant in terms "affirmative & positive change" of American Civil War [which btw, could be viewed as a failed war of independance by Southern States].

[Btw, one thing "Anti-war types" 'forget' is that Saddam could have easily avoided the War in Iraq- trying to paint the picture as Saddam being some passive character is laughable. To claim that America started this war is misleading- what America actually did was end it.]