The problem comes when people do this in the opposite order. "I'm a democrat and democrats believe X, therefore I believe X". A lot of people do this and it is a huge problem. I think it is just so much easier to do things this way, thinking through all of the issues we have to deal with is a big job and most people don't care enough to do it, so instead they just agree with the party line, whatever that happens to be. I really wish we people would just say "I don't know, I haven't thought about that much" or even "I don't care about that", but I think they are afraid of sounding stupid. They'd rather have an opinion, any opinion, than just leave themselves open.
The reality is, no one really agrees with every single opinion under any given label. It might be subtle, it might be a refinement, but there are places where you will disagree with the label. This is fine, the label should just be a way to quickly get some information passed at the beginning of a conversation, it doesn't have to be the end of the conversation as well.
A few years ago I heard this "no labels" idea, that people cling too closely to their political labels so we should get rid of them. The idea definitely has some appeal, but it seems to take things too far, labels do serve a purpose. It's nice to organize ideas together and work together with like-minded people, you just can't do this so blindly as everyone seems to want to. I think the right thing to do is identify with the group that seems to share your ideas as much as possible, but always be willing to challenge those ideas and even change labels if it becomes appropriate (whether that is because your ideas have changed or the party platform has changed). You should question ideas that come from people who share your label exactly as much as you question ideas coming from people of other labels. If you are a democrat who agrees with everything that Obama does and disagrees with everything that Boehner does, you are doing it wrong.
But disagreeing with our own group is hard. It is much easier to follow party lines and conform to ideas that we have thought about previously. And we identify with our labels for a reason, chances are a new idea under that heading will be to our liking anyway, it can be tempting to skip the step to verify this and just adopt this new idea before really giving it your full attention. This is fucking dangerous. This is how huge numbers of people wind up holding positions that are against their own interests. So what do we do about it?
1. Social Security
Now don't get me wrong, I love the idea of social security. People shouldn't spend their retirement eating cat food because they can't afford anything better. I think we should do as much as we can for the people who really need the help. I hate the idea of cutting programs and having people's needs not be met. But there is an economic reality that social security is screwed up right now. We basically have two options, cut a little bit now or a lot later. I would much prefer we do a little bit now.
The problem is, when the idea of cutting social security comes up, many democrats and liberals stand up and cry bloody murder. This is not because the proposal is unfair or the cuts are too deep, but just because the issue is on the table at all. If they want to pick apart a plan that is proposed and say that there are issues with it, I'm right there with them. It's quite likely that I would agree with many of their complaints. But I hate this idea that social security can never be cut, ever, no matter what. With this mentality there is only one option, wait until things get to catastrophic levels and then make much deeper cuts that we would have had to earlier.
2. Death Penalty
As I understand it, the humanist position on the death penalty is that it should be completely removed. The main argument would be that many people who are on death row have been exonerated. New evidence came up, maybe they had a terrible lawyer, who knows. It is also my understanding that death penalty is used much more against poor people. In general I think the death penalty is bad, I don't think it should be used very often. Almost never I would say. But there are extreme cases where I think we should just kill the guy. Any of these mass shooting that seem to be all the rage lately are great examples. If they go into a public place and kill 20 people indiscriminately and they don't kill themselves, we should just do it. There is no question that they are guilty and they have done something beyond horrible, I say kill em. Serial killers are another great example. The evidence needs to be absolutely overwhelming, but assuming we know for sure these guys are guilty, I say kill em. What do we gain by keeping them locked up for the rest of their lives?
One final thing I want to add here, this whole thing applies to people as well. If you are a big fan of someone and you listen to a lot of what they say, you should make sure it doesn't become hero worship. Do you love Dawkins or Hitchens? That's great, but I'm sure you disagree with some of their opinions, keep that in mind as well.