I'm a European and in my country driving tests are really hard and it takes a lot of very motivated people 3 or more tries and the better part of a year of frequent training to get a license. When I hear Americans talking about their driving test, most of them didn't even get on the road and did the test on a separate test terrain. All they need is knowing what a traffic sign is and being nearly able to use their highly automated car. The difference in required knowledge and ability is staggering.
Add to that the tendency to drive huge and heavy SUV 's and trucks that are highly dangerous to other road users and you get an extremely deadly situation.
Indeed, no need for large scale battles.