Last year I was nearly pushed off the road by a school bus just south of the Nashville area. I was on a fairly remote road with no other traffic. I confronted the driver and he told me "You just need to get off the road". Granted, I don't think it was intentional, but he misjudged my speed (which really wasn't that fast) and the length his bus.
Drivers don't think cyclists belong. Even school bus drivers who you think would have an extra sense of care are hostile towards cyclists.