The strained relationship between cyclists and motorists seems to be caused by a minority of selfish people on both sides - either behind the wheel of a car or on a bicycle.
Most motorists and cyclists would be happy to share the road and do actually take care when near each other. Your average law-abiding motorist or truckie would be horrified if they thought their actions were putting cyclists in danger. Many drivers do slow down when approaching a cyclist and, likewise, most cyclists I have encountered are cautious, polite, extremely safety conscious and know the rules of the road.
It is the minority on both sides who are inflaming a volatile situation where lives are literally at stake. And unfortunately - because cars are bigger than bicycles - most of those lives are cyclists.
It seems to have got to a point where these extremists on either side of the debate deliberately go out of their way to antagonise each other. Unfortunately this can cloud the opinion of the majority in either camp, who then label the other side as bad drivers or selfish cyclists.
Most cyclists I come across tend to ride in an orderly fashion and respect the traffic on the road, but every now and again you get some cyclists who take over the road simply because they can.