Before people get the impression that bikes in NL are always on separate bike paths, here are a few examples in Amsterdam:
http://goo.gl/maps/Sg5YW
http://goo.gl/maps/QkRY4
http://goo.gl/maps/Z2AVu
http://goo.gl/maps/STCyx
So why is it nice to ride around on a bike in Dutch traffic, because the city center roads are build to encourage low speeds for cars and because of the mentality that a bicycle is an accepted member of traffic.
I am now living in Maryland and what also doesn't help is that most people driving around got their drivers license, probably at the age of 16, and only had to show that they could drive around an empty parking lot with traffic cones and stop signs.