I don't live in the UK or the US but I found this pretty interesting and roughly matches how both countries appear to operate, at least to an outside viewer.
The polarization in the states between two groups which hate one another generates this type of culture war on every topic, it forces complicated issues to be split into a "for" and "against" type analysis, with each group going all in on whichever side their tribe picks. It also leads to somewhat inconsistent views (pro-life, pro-death penalty for example appear to conflict for example), and beliefs held so strongly that there is little room for compromise, everything is a battle with 'the other'.
In the UK they have their own issues but it seems like a much less divided country, which is amazing considering it is comprised of countries who at a national level have pretty much fought and hated each other for hundreds of years.
Tangent: On twitter a few months ago, Adele was called out by many in the US for cultural appropriation as she wore her hair in dreadlocks while attending a festival in London. The UK response by almost everyone appeared to be general confusion as to what she had done wrong with many "defending" her partaking in a multicultural festival.
If you live in a country where different groups are locked in a culture war, signalling the group you belong to, and abiding by the rules of the group become very important. The group discriminate, the group demands compliance.