Wow, now that's a total crock of shit.
I'm not buying for a second your "good vs. evil" scenario.
What I will buy is that there are good politicians (very few and far between) Dems and Pubs who, while they have their differences, are focused on serving their constituents.
The balance of the politicians, of both parties, are power mongering scum bags who care nothing but ripping off the electorate that they "serve".
Thus, until we get term limits and true campaign reform; we the people will continue to live in a dysfunctional political atmosphere.
I think 15 years ago, maybe, you could have legitimately made the argument that the two parties generally had the same or similar objectives (i.e., build a strong and productive society for the benefit of the citizens) but greatly disagreed on the best methods to achieve that goal (tax cuts vs, social safety net). Part of that difference in opinion about the best methods to achieve the goal was rooted in their differing ideas about how the economic system the government manages functioned (e.g., trickle down v bottom up). But at least since the onset of the Obama administration and the emergence of the Tea Party, the GOP has morphed into a reactionary power hungry grift machine, with no core objective, other than self enrichment. You could find individual Democratic politicians who only real goal is self enrichment, sure, but the party as a whole has a core philosophy and public good focused set of objectives, Republicans do not. The fact that one major party has no core societal betterment philosophy is the reason we live in a dysfunctional political atmosphere not the lack of term limits.