The problem is that what's "right" is not an absolute fact. Just look at things like gay marriage, prayer in schools, teaching of evolution/creationism, gun control and abortion. Who's right? The more progressive people will usually say gun control is the right thing to do, whereas conservatives will disagree. Christians and catholics will usually say gay marriage and abortion is wrong and that prayer and creationism should be part of our schools, whereas atheists will say the complete opposite is what's right. And it goes even further than that. What about woman's rights? Racial seggregation? We've come to the point that there's a general consensus on those, but there's still people (extremists, KKK, neo-na­zis, religious cults, foreign cultures...) who will have different opinions on them. There is no absolute right or wrong. Political parties are a way of reading a society's opinion on certain things, and then deciding what policy is the "right" one in the light of a society's stance on it.