> I'm not sure whether the political parties should have consistent ideologies.
It's something extremely important, along with "underlying theory of government" which you missed to address. If you think boundless inconsistency and shapeshifting are OK, you better say it straight - if you don't, you need a theory of bounds and it better be consistent.
> it's impossible for two or even three or four political parties to represent the diverse political views of over 300 million Americans.
That's upside down, in fact, 99% of Americans adopt a selection from the views offered by politicians and parties as reflected by the media. The "diverse political views" don't fall from the sky, they are products of the political system.
> Each of the two major US parties have always consisted of shifting coalitions of interests... [ consistent, stable views are just pretense ] when in fact the parties are demonstrably shifting coalitions of interests.
You are conflating "coalitions of interests" with "political views", they are quite different. In order to start a discussion we must separately and clearly define the coalitions, their interests and their political views: if they aren't consistently defined, neither accountability nor even basic security can be achieved.
If interests are a sufficient reason for dishing out pretense pseudo-rationality, then the coalition that is best at pretending and manages to accumulate a critical mass of power will simply enslave those who were gullible to believe them. I shouldn't have to explain this in America but here I am.
