Because the UK is in the middle of an awful delta surge. Cases : hospitalisations : deaths is much better in the UK than in the USA, and the latter are only as high as they are because the first figure is freaking huge.
From the JHU tracker- here’s the weekly cases and deaths from the UK
and from the USA:
The UK has been terrible at controlling the flow of people into the UK, not really enforcing quarantines at all. This let many cases of the Delta variant in, at almost exactly the same time as the European Football championships. That caused a huge wave, now we’re getting another as all restrictions are removed and kids go back to school. Still, the hospitalisations and deaths are manageable, because the UK’s vaccination programme did a great job of getting old people vaccinated, but did less well for younger people, who are now acting as the reservoir of infections and causing breakthrough cases in their contacts.