just wanted to add some context for the EU readers who I (perhaps mistakenly) assume have a bit more respect for government and for traffic laws in particular.

the US has a somewhat fraught history with traffic laws. by default, police are not really allowed to stop you for no reason and possibly search your vehicle/person. of course, this is very inconvenient for police, so over the years many traffic offenses have been created to remedy this. if a cop wants to (legally) pull over the most upstanding citizen in the country, all they have to do is follow them on the road for a mile and they'll have a reason.