One of the biggest differences I've seen between the US and particularly Europe is that the driving age here is 16 while the drinking age is 21. It's not quite the reverse in Europe, but it almost is -- most people there can legally drink before they can legally drive, and I imagine that plus viable public transportation options for most people make drunk driving less common.
Actually, in most countries in Europe you can
legally drive at 17 or 18 and
legally purchase drink at 18; in most countries it's legal to drink in private before 18. I'm sure there are better sources, but for speed (ok, and laziness!) I've used Wikipedia. Also, in many areas here, public transport isn't great either. If you live in an urban area, then you probably have access to reasonable public transport, but not in rural areas - which much of Europe is!
Digging a bit further, I came across an article on road safety from the
European Commission. Interestingly, their research found that age was not a factor in drink-driving.
That report also has a summary of
drinking habits in EU countries, which confirms the North/South divide in drinking habits: in the North of Europe, people will drink on fewer occasions but will 'binge drink', while in the Southern countries people will drink more often, but don't 'binge drink' ('binge drinking' defined as drinking more than the equivalent of 1 bottle of wine per day).
Thinking about it, and this is purely my own guess (so is quite probably wrong!), the attitude towards alcohol in the US reflects American culture, in that as a nation, America appears to be more conservative than much of Europe. For example, movies which would be an '15' (only suitable for those aged 15 years or older) rating here, may be 'NC-17' in the US. More extreme TV shows, like True Blood or Dexter are shown on select cable channels, while they're on mainstream channels here in the UK.
<Disclaimer> This is purely conjecture, based on my experience as a Brit, who has only been to America once (Orlando) and the impression I get from news coverage and popular entertainment and culture. Plus E-hell of course!</Disclaimer>