I mirror this situation. My wife and I had the opportunity to work in San Francisco for a couple of years. We're Australian.
The experience was great, but in the end, all the little things (health care, racism, homeless, political opinions, the ongoing wars, etc) added up and San Francisco is pretty liberal and open-minded compared to most of the rest of the US. We now live in Canada where the quality of life is great and we have public health care, so we don't worry about going bankrupt if we get sick. Don't underestimate how important that idea is to a lot of people.
For those Americans that are afraid of the whole spectrum of "socialist" political ideas all I can say is "don't knock it till you've tried it." While complete freedom is a wonderful idea, it often appears not to be practical when attempting to maximise the quality of life of a large population. There are certain freedoms that appear to be worth giving up (in countries like Australia and Canada, we haven't felt oppressed and it's nice not having to worry about people exercising their freedom to carry a concealed weapon).
In more socialist countries, it appears that the general concensus is that everyone gives something up to improve the quality of life for the whole. In the US, the general concensus seems to be that no-one should give anything up (even if they never use it), fuck you commie bastards. I always found discussions with that kind of attitude difficult. The "Team America" movie is hilarious because it's all so true to life.
Fair enough, I guess, but it doesn't suit everyone.