I don't think we should derive the centre from the existence or absence of extremes though.
In U.S that kind of left wing sentiment does not exist, i guess. So in those terms you are right that their center has been towards the right for a large duration now and thus it being almost the most free market country the definition of left would be more right than the normal than most other countries, i guess.
It is. Go have a detailed analysis of their economic positions of both parties - especially when it comes to government involvement in the economic workings of their country.
In terms of non economic issues though, i don't think their political centre is towards the right though. Many worst examples of extreme right wing around the world. I still feel on those terms their politics may have moved towards the right in recent times, but still the general public opinion is closer to center than right or left. Though those issues most of the time tend to be portrayed as Black and White most times, which i don't believe is the case.