I just read a very interesting article commenting Kant's statment that "democracies do not make war on one another." This argument had been used after the fall of USSR by one Fukuyama to predict the end of history.
Executive summary: It's bollocks. It's hard to define what democracy is, then you need to define what war is, and by the end you don't have enough samples to deduct anything.
My point of view: Indeed. Arguably the USA is a democracy yet they're attacking everyone they don't like (irrespective of those countries' government system). And anyway, there is no actual democracy on earth. At best, elective dictatorships.