Politics balances the ideal with the possible. In the first best world, we do the best thing assuming everything else about the world is ideal. In the second best world, we do the best thing recognizing everything else about the world will remain as dysfunctional as it already is.
Many political debates are because people disagree on values: I think a lot of freedom is more valuable than a little bit of safety, you may be more afraid, some people capitalise on that fear; I think the life of the unborn has value, you think a women’s body is her own.
Other debates occur because people cannot agree about the relevant time frame: I think earning more dollars today will solve tomorrow’s problems, you think we need to sacrifice economic growth to reduce pollution now.
A few debates are because people don’t accept common facts: I think very few people attended the President’s inauguration, he purports to believe it was the biggest ever.
Finally, some debates are because people disagree about the model of the world: I think most threats (future dangers) are home-grown, you think they come from outsiders. This relates to the last two, but is distinct because it deals with future facts, not something evidence-based.
Often political debates are about how much change is possible. This depends on the model of the world. If I vote yes now, we move somewhat in the right direction, but we release the pressure to move farther in the right direction. If I vote no, we don’t make the move, hoping a better offer will be on the table later. There is no guarantee this will occur, and in the meantime we may have lost some benefits. Say, in the US context, I believe in what a real Green Party* would stand for, but don’t think they will win, should I vote for the Democrats instead, which will be closer than the Republican alternative to my preferred outcome? Given the current US single-member district, first past the post, no ranked-choice voting system, that’s a logical choice for most environmentalists. They are choosing the second-best rather than nothing. I can make a protest vote, or I can try to move the system. If everyone in my district (admittedly I am thinking of progressive Minneapolis here) thought the Greens had a chance, they would act as if the Greens had a chance, and the Greens would have a chance. The possible is determined by what everyone thinks that everyone else thinks.
I believe there is no point in being a politician unless you want to accomplish something that improves the world around you. Sure some people get into politics for personal self-aggrandisement and wealth enhancement, but I believe for most politicians there is in the end no reason to accumulate power but to do something with it, that is to impose their values, their preferred temporal horizon, their perception of reality, and their model of the world on the government. Further, they must have the notion they can do this better than anyone else, not just better than a person in the opposing party, but better than the next best person in their own party.
Power is a means to an end, and usually the end is more significant than private wealth. Some politicians may forget this along the way, many try to combine their values with wealth-enhancement, but hopefully they remember near the end of the careers the whole point of doing what they did and expend some of their power to achieve their original aims.
It is the advocate’s job to move the politician in a particular direction.
It is the politician’s job to compute how far to move both to maximize future power by ensuring his constituency is along for the ride and to actually move in the ‘right’ direction consistent with the reason for being a politician in the first place.
* The US Green Party at the national level is of course highly problematic from an environmental and political perspective.