As folks have said, a lot of times these issues are simply 1 person not showing courtesy or common sense towards another person. In the case of secondary streets with stop signs as controls, or with no traffic controls that is certainly the case. As you have all said…If everyone makes an effort to be both cautious and courteous we'll all get where we are going without too much delay. As to why we seem to have dropped courtesy and caution when we approach each other...I don't have a clue. Perhaps as CD and BR have suggested it is an overdeveloped sense of entitlement. Perhaps it is lead in our water. Or we were all dropped from a height shortly after birth in a giant hospital based conspiracy to incapacitate the nation. <smile>
But, in other cases it seems we have set the traffic system up in a way that creates conflicts.
For example, take 24rth/Shilshole and Market in downtown Ballard (actually..this is true on most of the Market Street Intersections.) If you are traveling east on Market and you want to turn onto Shilshole there are issues. This intersection has a lot of pedestrians. When the traffic light is in the favor of the east bound driver you also have an east/west bound walk light active. So drivers trying to turn onto Shilshole have to yield to the pedestrians. During busy times pedestrians are scattered everywhere and the stream of people across the intersection is constant. If you get one or two cars able to turn in a light cycle that is good. You end up with a long line of people in that lane, all growing impatient that they just watched a relatively long light cycle in their favor go by and they haven't moved much. The traffic pattern is set up in such a way that the walk light and the traffic light conflict. Not good. Small wonder people get frustrated and rush the pedestrians. And…my guess is that by the time they approach the next intersection with less control on it they are still wired from their frustration at that last light, and so are less likely to be courteous or show restraint and common sense. Their fuse is a bit shorter perhaps.
It might make more sense in these cases to change the light cycle to one that has an all way crossing for peds. Once during the light cycle peds get the walk light in all directions. ALL traffic is stopped to permit this. Then for the rest of the cycle Peds have a red walk light and traffic is permitted to move in the normal cycle.
The city instituted this downtown in a few places and at least the few times I go through those intersections it made a huge difference. Drivers were not presented with a generously timed green light that they couldn't use. Peds were crossing the street without worrying about traffic trying to turn. Things became more predictable and ordered. The change was a programming change and didn't involve the installation of expensive equipment that I am aware of.
I don't know how you install a greater awareness of courtesy and common sense into people to take care of the intersections with lesser control, but certainly those intersections that have a greater degree of control can be examined to see where the frustrations are really coming from. Perhaps if you can reduce the frustrations in those areas people will approach other intersections with less built up frustration and think more courteously.
I also have a lovely bridge and a few parcels of swamp land for sale if anyone is interested? <grin>