Peggy Noonan in the WSJ:
I do not feel America is right to attempt to help spread democracy in the world because it is our way and therefore the right way. Nor do I think America should attempt to encourage it because we are Western and feel everyone should be Western. Not everyone should be Western, and not everything we do as a culture, a people or an international force is right.
Rather, we have a national-security obligation to foster democracy in the world because democracy tends to be the most peaceful form of government. Democracies tend to be slower than dictatorships to take up arms, to cross borders and attempt to subdue neighbors, to fight wars. They are on balance less likely to wreak violence upon the world because democracies are composed of voters many of whom are parents, especially mothers, who do not wish to see their sons go to war. Democracy is not only idealistic, it is practical.