A culture has developed in which people have the option of picking facts based on their political beliefs, instead of the other way around. The current debate over gun control is a testament to this trend.
The "party" in this case isn't blue or red. It's the media that, whatever its orientation -- right, left, or down the middle -- can agree on one thing: We're increasingly a country of people who want to choose up sides, go to our respective corners, and throw things at one another.
Do traditional news outlets falter? Of course they do, all the time. And opinion does color the facts. But that is certainly no excuse to choose to expose yourself only to the work of journalists who you know share your political inclinations.