Whilst it is, as you hint, inappropriate to generalise whilst discussing policy due to the subject's complexity, I believe it is entirely appropriate to do so whilst discussing politics.

This is because the strength of a political faction (or its united subset) grows with the square of its size, and because the winning strategy in iterated prisoner's dilemma is tit-for-tat.

The former reason stabilises the system towards two roughly equal sized parties fighting for power and slowly iterating towards where the people are standing politically (compare the respective positions of Johnson and Goldwater in 1964, or around FDR's new Bill of Rights, to today's discourse) and moves away from discussing ideas and towards the behaviour of sports teams in a high stakes championship.

The latter reason means that if one side lowers itself to base populism, the other has to follow or lose the race. This cheapens the discourse and encourages simplification and the discussion of trivial matters (such as ideas no longer relevant, or high visibility but low impact "Cecil the Lion"s), whilst the civil service quietly takes care of the business of government. Panem et circenses.

Thus, people choose a camp, and rationalise their views accordingly so that they align with whatever the party is selling at the moment. This is, game theoretically, the most efficient use of their person for the cause since if they do not tit-for-tat, the other side will be stronger and win the argument.

It does not even make sense for the average person to think too hard about issues since they have such low visibility of them. How can someone who has never left the USA and whose town consists of 7th generation Swedish immigrants understand immigration and global competitiveness in a world where billions, equivalent to the entire US population several times over, are entering the middle class? How can one have a sound opinion about the Ukraine or Israelo-Palestinian conflict when both sides' intelligence agencies are doing their best to intoxicate public opinion? Whilst the NSA is now famous, how many of the general public know about the NRO, or have any idea how the roots laid by Soviet Active Measures distorted yesterday's zeitgeist and influenced today's? This is a subject Kissinger talks about many times in his works: that he had "no idea" and as he gained higher and higher clearance, his views changed.

But the senior party members do have access to the information (or as good as the alphabet soups can provide, anyway) and are supposedly meritocratically selected for their shrewdness, so what they decide is probably the best for the party. What is the fastest way to get the electorate to follow you? Shape the discourse with simplifications, red herrings, wild goose chases and The Donald's hairpiece. Let Fox News lead the GOP lot, let CNN lead the Democrats (or however you want to split your groups). This way, you manoeuvre House of Cards style into a position that optimizes your own, whilst not giving away too much of the country's future.

Personally, I think it is that last bit that the current generation of Washington residents is getting very wrong, because they do not see the bigger trends or think they'll be long gone, or the changes too gradual to be noticed and result in unpleasant circumstances for them. Like the Brits and the French they might find themselves swimming naked as the tide goes out... I could write for hours about it, but that would be off topic. Just thought I'd throw this in.