Don't get too carried away. Being a democracy doesn't make you invincible, you can't take the democratic success idea to be an absolute rule. The form of government is a moderately-important factor when weighed up against other things in determining how a war will come out. Most studies show democracy to be the best form in this respect, although there is also a tendency for the most authoritarian regimes to do pretty well, so the consolidation of the government in question has also got a lot to do with things.
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