There's a theory that Democratic governments don't invade other Democracies. You can read the Wikipedia article Here. You can also read about the various wars between democracies in this page. This is a great analysis of the issue. There is a counter-argument for each of the examples, largely claiming that at least one of the parties was not a Democracy. Under the objections in the article, it seems that there aren't many Democracies to go to war in the first place. If you can exclude any nation that uses political officers to ensure that a party retains its power, then I doubt there are any democracies in the world.
Let's look at Nazi Germany. They rose to power in democratic elections, and they went to war. Critics will quickly point out that by 1939, there was no Democracy left. It seems to me that we shouldn't say that "Democracies don't wage war against each other", we should say, "Democracies coincide with peace and stability". After all, if a nation is strong and stable enough to hold together a strong Democracy, you can be assured that most of the motives for war are already satisfied. Instead of Democracy stopping wars, both wars and un-democratic government have similar causes: poverty, corruption, desperation.
But who cares? We are already in favour of Democracy, since it's a superior form of government to any of its known alternatives. People aren't trying to pin the name of Democracy on nations like a talisman to end wars!
The only problem is that people are doing just that. Tony Blair, in an interview about the motivations for invading and occupying Iraq, said again and again that "Democracies don't go to war". He doesn't seem to understand that it's all too easy for an impoverished people -like the Germans of the 1930's- to throw away their Democracy for some perceived security.
PS. Tell me where I quoted Darth Vader in this essay, and you get a point!
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