Democracy has a Built in Pressure Release Valve
I remember the first time I saw a picture of a steam engine governor. The device is ingenuous: its very design relies on the laws of nature to maintain a relatively constant speed. A rotating shaft, driven by steam, is attached to weight-bearing arms that hang down by its side. As the rotational speed increases, the centrifugal force causes the arms to swing outward, thus dampening the rotation of the shaft. The faster it tries to go, the more force prevents it from going fast. Anyway, the point is that, rather than an external digital controller, as we might build today, this old design is self-regulating.
It seems to me that democracy has this self-regulating property. At any given point in a nation, there plenty of people angry at the government. It builds up pressure, sows discord in the nation. A monarch or dictator would fear this pressure. But in a democracy this pressure is relieved by the act of voting, and all the political rituals (debates, etc) that go along with it.
What's interesting about this is that it works regardless of whether or not "democracy" actually means that people control the fate of the nation. Modern American government is controlled by political parties, congressional voting blocs, and lobbying organizations -- all of these are persistent, non-democratic entities. The real muscles which flex power in our country do not answer to voters.
And yet, we feel as if we control the government, because every four years we get our chance to "vote the bastard out" if we're unhappy. Even if that act only amounts to changing the kabuki mask worn by the thousands-deep organizations that actually constitute power. The mask is important -- it sets the tone and tenor of delivery, and has veto power -- but ultimately it is just the presentational interface to a vastly more complex body behind it.
This is an interesting property of democracy when compared against systems which maintain a narrative of "we're in control because we know what's best for you" such as communist regimes. There is no built-in pressure release valve in those narratives. When you get upset at the government, how can you vent your steam?
Perhaps this is why communist regimes work so hard to censor information. With no built-in pressure release valve, they have to either construct an artificial one (as North Korea does, using the USA as its Emmanuel Goldstein) or sit in fear that their citizens will boot them out French Revolution style.
Democracy idealized inspires us. Democracy ritualized mollifies us.