If you really want to understand how we came to today's War in Ukraine and what made Putin believe that he could invade the rest of Ukraine and absorb it into his dream of a Greater Russia, all without consequence, watch this:
The Russians have a limited number of modern counter-battery radars, and are having a very difficult time getting Western-made electronics needed to build more, so losing one of these hurts. The US and our allies are providing Ukraine with numerous cutting edge versions. It's making a big difference on the battlefield.
After thinking about this, not sure why this fuel truck didn't have an escort. Or maybe that's just how bad it is for Russia. They either can't afford the resources to escort or the leadership is utterly clueless or both. Probably both.