US ATC is way more helpful and less judgemental because pilots in the US have a predisposition towards distrusting them. Anybody who grew up in the US knows an agent of the Federal government is very likely to be perceived as an adversary, so ATC feels the need to go in the opposite direction and promote their willingness to serve. I think they feel slightly uneasy in their power, like necessary but distrusted intruders into daily life, and not so entitled as they might. In other words, precisely as the US founders intended that Federal government would feel. If only the same would apply to those working in Fortress Washington DC.
In my experience, that slight insecurity in being Federal employees does work as intended for the benefit of the pilot who chooses to contact FAA ATC.
Silvaire, from my single data point, but having flown in both the US and Europe, I would agree. In general US ATC seems better trained, and of a more even quality. There are some excellent ATC resources in Europe, but having experienced start up delays (which disappear if you are lucky to speak the local language fluently), left on a radar vector towards high ground, bossy ATC unsettling students, way too much verbiage on air ground facilities: however, flying in Europe has helped raise my situational awareness as I double check what ATC is asking me to do.
