As a cyclist it happens all the time, it goes something like this:

1) A car comes within centimeters of side swiping me and knocking me down. They don't even notice I'm there.

2) They stop at the next traffic light, I tap on the window to tell them to be more careful.

3) They get angry at me.

4) Other drivers see this interaction and soon you see articles in newspapers complaining about "militant cyclists"

As a pedestrian in SF, I feel a lot more threatened by cyclists than by cars. The car-pedestrian right of way rules are clearly established, but the pedestrian-cyclist rules, if they exist, seem to be ignored by cyclists. I have numerous times had cyclists bike 2 feet in front of me instead of stopping at a pedestrian crossing. I am not sure cyclists in SF grok the idea of a stop sign either. Same thing with traffic lights, which a lot of cyclists treat as mere suggestions.

I mean, around me the made a law that you can't be within 3 feet of a cyclist. After that passed there was a group of cyclists going around with yardsticks trying to smack cars while riding.

Pretending that there aren't extremely toxic cyclists doesn't help the problem.

I LOVE this idea. Don't want your precious car scratched, then give 3 feet. My street has no sidewalks and cars constantly exceeding the 25mph limit. I'm pretty sure I could damage some vehicles doing nothing more than holding my house keys sideways in my hands as I walk/run. Drivers truly don't care about anything outside their windshield.

They were actively riding into lanes and hitting cars.

Cyclists will often ride between rows of cars that are stopped at a traffic light in an effort to get to the front, probably assuming that the 3 feet law doesn't apply in that case.

Cyclists don't have to be toxic for the whole setup to not work, they just have to not obey the same laws that are in place for cars. Where I live, I'm more likely to be hit by a cyclist on a pedestrian crossing than by a car.

What a strange double standard. Presuming your anecdote is true (and statistically, it isn't), your greatest risk is minor injury if hit by a cyclist, while that's the best possible outcome from an interaction with a car.

And no, cyclists don't often ride between lines of cars. Some cyclists do that. Just like some drivers are reckless jerks.

Every group has bad actors. I'd even wager both groups -- cyclists and drivers -- have the same percentage of morons.

You seem to be claiming that all cyclists have to be saints "for the setup to work", which is bizarre. The rules in most cities in the US clearly prioritize cars over people. As plenty of other cities around the world have demonstrated, changing those priorities changes behavior.

In SF, I see cyclists jumping traffic lights, ignoring STOP signs, not giving right of way to pedestrians in the cross walk etc. etc.. In my anecdotal experience I see more cyclists breaking traffic laws everyday than cars. I havent felt the same way in other American or European cities, so its possible this is an SF only thing.

From my experience, it's all too common in Boston, too. Zero regard for traffic signs, lights, or pedestrian activity. It's usually the couriers that ride unsafely.

In London riding to the front is actually encouraged, if I understand local traffic mores right. (And it seems like the sensible thing in any case.)

Yes, this is mostly my experience as well. I had a delivery truck driver get out and start yelling abuse because I banged on the back of his vehicle to alert him that he nearly knocked a woman off her bike a couple days ago.

This isn't rare, either - there's at least 1 shouted interacted per week.

It's no wonder my friends are afraid to get on the roads/their bikes.

Ha, I remember knocking on the rear windscreen of a car as it passed me by, I was doing about 20mph, the car not much faster, I didn't even need to stretch my arm to do so. The driver pull over further down the street and I had a conversion with him very calmly, he wasn't happy about me knocking on the window and told me that if he was younger he'd punch my lights out.

I used to do this all the time as well, and then I started noticing that it only increased the rage that I felt and also the rage in the other drivers. It finally came to a head when a car tried to run me down between multiple lights.

My new form of riding in the city is to be 100% defensive all the time, but not in a give up my rights as a cyclist way. I assume cars will do dumb things (because they always do) so I avoid their blind spots, never pass on the right, alsways take the entire lane so that a car can not pass you if it's not safe (only do this in the city), when traffic is slow assume cars will jump quickly around in lanes etc.

Many people get angry and defensive when you yell at or reprimand them. The goal is to try and inform them of their poor driving without increasing anger on both sides. Now I do this with a look, and no anger, and people tend to respond to that apologetically.

Any vehicle that is close enough for me to touch I hit. There's no reason to drive that close to a human being who doesn't have hundreds of pounds of armor around them.

I did that when I was nearly hit in a marked crosswalk (they didn't slow down and were less than arm's length from me) that was at an intersection with no light. They went around the block to come back and start threatening me for hitting their car...