I think you have to ride defensively as well as drive defensively.
I think it is crucial to know what to do when a car is being harrassing or threatening. If it means you have to get off the road because otherwise you might be sent off the road, then I think we need to do it. I think the majority of drivers are fairly respectful of us riders, but we can't just assume that a.) they understand us and b.) that they will be courteous.