The idea that success and failure go hand in hand is not unique to democracy. It is part of the human condition. It is the essence of tragedy. Hubris can accompany any form of human achievement. The most gifted individuals are often the ones who overreach themselves. Having great knowledge is no guarantor of self-knowledge: intelligent people do the stupidest things. What is true of individuals is also true of political systems. Empires overreach themselves. Successful states become arrogant as they revel in their successes, and they become complacent as they rely on past glories to see them through present difficulties. Great powers decline and fall.
However, the democratic predicament cannot be reduced to the general run of human tragedy, and it is not just another stage in the great cycle of political decline and fall. Democracies suffer from a particular kind of hubris. In ancient Rome, triumphant generals were accompanied into the city by slaves whispering in their ears that they too were mortal. Democracies don't do this to their heroes, because they don't need to. Successful democratic politicians are constantly being reminded of their own mortality. They can hardly get away from it: the most common experience in a democracy is to suffer abuse, not idolatry. No democratic politician can reach the top without getting used to the catcalls of the crowd. That is why no one in a democracy should ever be taken unawares by failure. If democratic politicians become complacent, it is because they have become inured to the whispers of mortality, not because they have been shielded from them. Autocrats are the ones who are taken by surprise.
The definitive image of a modern autocrat confronting the catcalls of the crowd came when Nicolae Ceausescu stood on the balcony of the Central Committee Building in Bucharest on Dec. 23, 1989, three days before he and his wife Elena were executed by firing squad. He looked genuinely puzzled: what is that noise? No democratic politician ever looks puzzled like that. The look that sums up democratic complacency is different. It is the face that defeated incumbents wear on election night (think George H. W. Bush in 1992). They don't look surprised but they do invariably look hurt. Yes, they seem to be saying, I heard the abuse you have been directing my way. How could I not? I read the newspapers. But that's democracy. I didn't realize you really meant it. That look is one reason why democratic life is more often comic than it is tragic.
What is true of individual politicians is also true of democratic societies. Modern-day America is sometimes compared to imperial Rome, since it has some of the trappings of an empire with its best days behind it. But the United States is not Rome because as well as being an empire it is also a functioning modern democracy. That makes it too restless, impatient, querulous, self-critical to qualify as a candidate for late-imperial decadence. Democracies are hardly oblivious to the impending prospect of catastrophe. If anything, they are hypersensitive to it. One of the hallmarks of present-day American democracy is its endless questioning of its own survival prospects. The problem for such democracies is not that they can't hear the whispers of their own mortality. It's that they hear them so often they can't be sure when to take them seriously.