I'm not sure about that, I'm from the UK and most of my exposure to US culture comes from the internet or the media but I get the impression that there are simply more extremes of opinion in the US than there are here.
Your liberals are more progressive and your conservatives are more conservative, at least towards the fringes.
I think it would be much easier to find a consensus of opinion in the UK on most topics than it would be in the US.
It might be true that the political status quo (on many issues) in the US is further to the right than it is here, but that might be because progressives feel that they have to vote for the party that most closely represents their views and has a chance of being elected (presumably democrat) rather than a party that they necessarily agree with.
I think the UK is somewhat a special case among the Western European nations in this context as well. From a Finnish/Nordic perspective it seems that the US Democrats, on average, seem only a bit to the left of what would here be regarded as "center"; in some cases even to the right.
Your liberals are more progressive and your conservatives are more conservative, at least towards the fringes.
I think it would be much easier to find a consensus of opinion in the UK on most topics than it would be in the US.
It might be true that the political status quo (on many issues) in the US is further to the right than it is here, but that might be because progressives feel that they have to vote for the party that most closely represents their views and has a chance of being elected (presumably democrat) rather than a party that they necessarily agree with.