The recent discussion of the Censure of Pat Meyering suggested a sub-context to the differing views. I have been thinking how that came out of human evolution.
Evolution: Go back several million years to our early ancestors. They were more likely to be prey than predator. Hominid's almost unique ability to see the color red probably comes from the fact that new tree leaves (sweeter and less acidic than mature leaves) have red veins - suggesting mostly vegetarian life. Our ancestors were likely small (more like Capuchin monkeys than Great Apes) and like most species found the trees safer than the ground. If you are swinging from tree to tree by your hands you really need 3-D depth perception or you'll be falling a lot. (If you are throwing your entire body at a tree like a squirrel, you can afford to be off a little bit, as long as you have sharp claws to catch onto the tree.)
This implies hominid eyes have to be facing mostly to the front to allow enough vision overlap for each eye to provide 3-D depth perception. But individual prey animals want as close to a 360 degree vision as possible (like rabbits) to enable them to spot predators.
Hominids gave up the 360 degree vision for the depth perception. In order to compensate, hominids formed tribes so what one couldn't see, the others in the tribe could. So if the tribe is the guarantor of your safety, then you owe your life to the tribe and must do everything to support it. And that means you cannot compromise with another tribe over territory because to do so would mean less food for your tribe.
Now tribes become political parties and one is committed to that system of beliefs. You cannot concede that the other party/tribe might be even partly right about some areas because to do so would appear to abandon your entire system of beliefs. There is always the danger the other tribe would yell something like "HA! You admit we were at least partly right about one thing so you must concede we might be right about other things!" So partisanship has people contorting themselves in mental and verbal knots to not admit the possibility of any weakness, or error in anyone or anything in their tribe.
As to the City Council, CM Moylan and CM Griffith are Democrats, while CM Whittum is a Libertarian. So loyal Democrats feel the need to support their tribe,regardless of how they feel about campaign contributions on the national level.
But for Sunnyvale, this is silly. A Libertarian majority is not going to put Sunnyvale on the Gold Standard and a Democratic majority isn't going to nationalize the steel industry.
I voted for both Moylan and Whittum and overall, I am glad I did. They both seem to work together towards mutually shared goals I support and both sometimes make mistakes. I.e., anything I disagree with is by definition, an error (but I am a forgiving sort). City governement is about garbage collection and parks and paving streets and such. National political alignment has little to do with any of that. So it is possible to concede your guy is wrong in one thing while being right about most other things.