I dunno what gave you the idea that the UK was less racist than the USA or France. Race relations are... different here in the UK than in the states. British identity is coded exclusively white. There is an assumption that "British values" are a thing that exists, and that, for example, Islam is incompatible with them. In general, the conception of what makes someone British is very narrow, whereas US identity is necessarily broader. On the other hand, our cops don't generally make exterminating non-white people their primary goal.
I distinctly remember a Labour MP - I think it might have been Yvette Cooper actually - going on BBC Newsnight... This was maybe ten years ago... And saying, point-blank, that multiculturalism had failed. This was in the context of David Cameron banging on about instilling British values in prospective immigrants and the need for "integration" (conformity) and the like. It was the moment Labour lost me and become a for-the-whites party. This was before Corbyn even. Labour saw their record on immigration as something to apologise for.
For the past five years, to distract from the terrible failures of neoliberalism and austerity, both main parties and our entire media establishment have laser-focused on the few thousand "small boat" refugees that arrive on our shores from countries we've bombed and sanctioned. It was, for some reason, the dominant issue of the election, and prior to this, the key benchmark on which the Conservative party was being judged was in their ability to enact a performatively cruel plan to deport refugees to Rwanda while their claim is being processed (keep in mind, for example, that some of these refugees will be turning up because they're gay, and Rwanda does not enshrine their protection against discrimination and public attitudes towards homosexuality are negative). Both parties pledged to "stop the small boats". Keep in mind, the spectacle of small boats only exists because the UK refuses to allow people to claim for asylum from afar. Anyway, on the first day of these riots, what were people chanting? "Stop the small boats". The media's response is to suggest that it's all Russia's fault.
But yes, also as Awoo says, there is a violent subculture that exists within British society that is always itching for a fight regardless, and that might be a key difference as well.
Every day I wake to the news that Biden hasn't yet contracted ebola and feel dispair.