Anecdotal data is very misleading

Lots of people travel to Europe and then come back and rave about how good the drivers are in other countries and how politely they treat cyclists. I'm in fact one of them. However, I've had extremely poor experiences in Italy, where the only time I got buzzed in all of Europe was down the Italian side of Tenda pass, with the other lane completely clear and free. Even in
California this doesn't happen to me. In an effort to understand the statistics, I took a look at a few web-sites.

An examination of european cycling statistics shows that the Italians are by far the most dangerous to cyclists in all of Europe, followed by the British and the Austrians.

By contrast, the US is at 0.2 fatalities per million mile (source here). Translating that into the kilometer chart provided in the Europen statistics link, that would be 12 fatalities per 100 million kilometers, which isn't a whole lot worse than the Italians (who are at 11 fatalities per 100 million kilometers).

According to the California Highway Patrol Integrated Statistics, cycling in California is no worse than cycling in other parts of the USA, after correcting for the fact that more cycling happens in California than in many other states. In fact, the statistics point out that it's probably considerably better.

All in all, my suspicions are confirmed: the two worst countries to ride a bike in are the US and Italy.