In any political system it is necessary to give some people the power to make laws and to enforce them. For reasons of practicality that power is often given to just a few people. This of course raises the question: how can we restrict the exercise of that power? The people who end up with power are motivated by personal interests as well as the interests of the state, and naturally they will be inclined to use their power to further their personal interests, and not just for the good of the nation. Obviously we can’t just make a law forbidding them from misusing their power, since they have the power such a law is just words on paper, it has no force.
The naïve solution is to trust the people as a collective to prevent a misuse of power. I call this the naïve solution because it works only in very rare cases. A practical problem is that the average person simply doesn’t have the resources to stand up to modern military power (unless you all have been keeping a stash of surface-to-air missiles in your closet without telling me). There are also problems with the idealistic assumption that people care enough about liberty and justice to take up arms if the government violates these principles. People do care about these things to some extent, but they care more about their quality of life. So as long as the government promises to let them keep whatever good things they have, and not to step on their toes, then it can misuse its power as much as it wants. Similarly people will support a misuse of power if they are promised something in return (Caesar’s seizing of power is an example of this). I know I sound cynical for saying this, but it’s my observation that as long as people are happy with their lives then they aren’t bothered by injustice. After all, the American government tortures people now, and there isn’t any rioting in the streets as a result. Various revolutions may sometimes be cited as counterexamples to this principle, but those revolutions share two features. Firstly many of them are an attempt by people to improve their quality of life (they feel that those on top are making life worse than it has to be). And secondly revolutions against foreign powers are motivated primarily by the desire of local authorities to have the power instead of foreign authorities, talk about rights and unjust foreign rule is often just that, talk.
A better solution is to try and divide the power among a number of different people. Ideally they will all have different interests, and thus will pull against each other, so that no one person or group of people is able to take control. This is a better idea, but it too is flawed. One problem is that the balance is never perfect, and so in some systems it is theoretically possible for one person or group to take all the power, even within the constraints of the system. In the American system the presidential pardon is such an imbalance. In theory the president could simply order all the politicians who oppose him assassinated and then simply pardon the assassins. We hope he wouldn’t of course. But even if the balance is perfect there is nothing that stops the people in power from colluding. A balance only works to restrict power if the people the power is divided among really are pulling against each other. If they agree then they can collectively choose to ignore the rules. And things such as political parties only encourage this collusion.
Perhaps most basically we have to wonder why the people at the top simply don’t get together and rewrite the rules whenever the rules get in their way. After all, they have all the power, so they could simply declare any rewrite legal. The primary obstacle is internal. Politicians are people too, and I am a bit of an optimist about human nature; not everyone is evil. The reason politicians simply don’t revise the rules to give themselves unlimited power is because they believe at an almost instinctual level that doing so would be wrong. Of course not everyone in the government is equally restrained, but since most governments do include some kind of mechanism where the power is divided among different people the best and worst tend to balance out. But this doesn’t solve all our problems. The problem with these internal restraints is that they aren’t fixed based on some eternal and unchanging standard, rather they are developed by absorbing the attitudes of those around them about what is and isn’t acceptable behavior for a public figure. So if you call politicians corrupt you will end up with corrupt politicians. Which may lead you to believe that politicians are exceedingly corrupt, which will lead to exceedingly corrupt politicians, and so on (we are caught in such a cycle now I think). You see the internal restraints are based on what people perceive as normal (as people feel uncomfortable deviating from what is seen as normal). So if we all thought of politicians as examples of human perfection then anyone who was a politician would feel that being less than perfect was unacceptable, and they would have to force themselves to cross that line (of course perfection is too high a standard, and would cause its own set of problems, since forcing people to cross that internal line makes them more likely to cross it again). But if we all accept that politicians are corrupt, take bribes, and are swayed by special interests then that is exactly how they will be, because someone who becomes a politician with that attitude that such behavior is normal won’t balk at doing any of those things. (All of this of course rests on the psychological fact that there are strong psychological forces that motive us to act as the majority of people expect us to act. There are also higher level, and thus less instinctual and more intellectual, forces which govern our actions, but they have to work hard to overcome our natural desire to act “normally”, for better or worse.)
Which leaves us with a problem. Given that our politicians are corrupt what can we do? Simply recognizing how corrupt they are makes the problem worse in the future (partly because the next generation sees how much the last one got away with, and then goes a little further than that). But neither can we bury our heads in the sand and pretend that there isn’t a problem, because that will let the people in power feel that they can get away with more (given that their attitudes about how they should act in office are already formed a change in our attitudes won’t immediately change them). Ideally we would clean house and replace them with a better bunch, but as far as I can tell there is no better bunch to replace them with; they all sound equally good on paper and all act equally poorly when in office. Thus we are stuck.