In all of my years of cyling, and in different state, both urban and rural, humans with violent tendancies were never a cause for alarm. Instead:

1) Bike around a curve on a rural road and there is a brush fire with flames leaping as high as my bike and the asphalt of the road is bubbling under my tires. Solution - sprint.

2) Bike down a steep hill. In the opposite lane was a pickup carrying a load of old washing machines, driving up the hill. Behind me I heard the mechanical crashing noises of washing machines falling out of the truck and bouncing down the hill towards me. Solution - sprint.

3) Biking on a rural road. Speeding towards me in the opposite lane is a large farm truck with high sides in the back, billowing smoke over the top of the cab. The truck makes a sharp turn to its right, into a farmyard, and the side silhouette shows me that the contents of the back of the truck are in flames, with the flames shooting high. The truck slams to a stop in the farmyard, and the driver gets out and runs. One quick glance shows me that the fire engulfed vehicle parked next to a propane tank. Solution - sprint.

My motto is to bike light and be able to sprint when necessary.