First of all confirmation bias has been well studied and is a documented psychological effect. I know you have some bias against wiki but I really doubt you want to read through primary research so I'll leave this here. It's a really good summary of the confirmation bias theory and has some explanations of the large body of research that has gone into testing this theory. It's really well sourced and it actually talks about how confirmation bias leads to the polarization of opinions on such topics as, yeah you guessed it, politics.

As an example here is this excerpt of a relevant study :

Charles Taber and Milton Lodge argued that the Stanford team's result had been hard to replicate because the arguments used in later experiments were too abstract or confusing to evoke an emotional response. The Taber and Lodge study used the emotionally charged topics of gun control and affirmative action.[26] They measured the attitudes of their participants towards these issues before and after reading arguments on each side of the debate. Two groups of participants showed attitude polarization: those with strong prior opinions and those who were politically knowledgeable. In part of this study, participants chose which information sources to read, from a list prepared by the experimenters. For example they could read the National Rifle Association's and the Brady Anti-Handgun Coalition's arguments on gun control. Even when instructed to be even-handed, participants were more likely to read arguments that supported their existing attitudes than arguments that did not. This biased search for information correlated well with the polarization effect.

So what else do you want at this point. I have definitively proven that confirmation bias is a valid scientific theory, it is a much better descriptor of the original point that you were trying to make. You mistakenly used the concept of repression, which is only really used as a concept to study repressed memories. This concept does not at all apply to the polarization of our political system and you have not given me a single argument for why repression is the correct psychological concept to use here.

Finally, I appreciate all of your pejorative comments but they have added nothing to your already underwhelming arguments and they just make you look like an asshole.