They represent the interests of an economic class, or more accurately, a temporary coalition of allied economic classes. I'm not implying there is anything intrinsically wrong or sinister about this, its just the way things are. History and politics can best be explained as the formation, coalescing, breakup and conflict of social and economic classes. And it is no coincidence socio/economic boundaries very often coincide. Classes share common interests which conflict with the interests of other classes. In fact, that is how we define the word "class".

It's perfectly natural for even honest people to tend to feel that what's in their best interest must also be in the best interest of society as a whole. They also tend to ally themselves with others who have the same interests they do, even if those people are sometimes their competitors and rivals. All aristocracies fight each other, but when faced with a common threat they tend to unite and work together.

There is nothing unexpected or evil about this. It is elementary group dynamics, probably inherited from our hominid ancestors, and reinforced by our economic organization. The immorality begins when we forget about this natural order and start justifying our behavior with principle, ideology, religion, ethics, and other superstitions. The only true, valid and practical ethical morality is the Golden Rule. Strive to follow it, and beware those who don't.

A wise man does not hate his enemies, he knows they are not that different from him. He seeks to understand them and reason with them, educate them and learn from them; to seek common ground, negotiate and compromise. Visit your enemies, go with trumpets and banners, pomp and ceremony, to show you are not trying to creep up on him. But never walk into their camp alone and unarmed.