Even cows can be dangerous if you make them mad.

Of course but bison are way less predictable and don't have 10K years of selective breeding for docile behavior like modern cattle do.

I saw one take a rearview mirror clear off a car with a lazy flick of its head, while walking past without breaking stride, just because it didn't like something about the car.

As Sean Connery says in Hunt for Red October, "We must give this American a wide berth."