The survey was conducted in 2017, where a set of consumers recorded their reasons for the enthusiastic attitude towards driverless vehicles. Since the aim of AVs is to provide solutions to traffic problems and make elderly and disabled people work more independently.
In my opinion, the US seems very welcoming towards new technology and does not fear to take a leap of faith and be more futuristic. It also shows awareness about the driverless car is high and acknowledged with a positive mindset.
Source:- Statista