I think the larger problem is the nature of current political discourse is to assume the other person/party is an evil idiot and do everything in your power to spread that idea, without addressing the content of what they say or proposing any details better solution yourself or working together to for the good of the country instead of infighting.
Good point. I wonder how much of that is due to the long period of peace and prosperity that the U.S. has experienced; in the absence of any serious external threats, it becomes easier for partisans to squeeze their political opponents into that role.
9/11 was an anomaly. Following the attacks we saw a time of genuine good will between the parties. The further we get from that date, the more our politics is descending back into petty partisanship.