Agreed. It seemed obvious, I think.
It may be protocol that the Queen's security takes priority in this case, therefore, it would make sense that the vehicles bringing visitors to the castle would be British security.
You would have to compare it to other presidential/foreign leader visits.
Thanks for the history lesson about past visits. Sorry about my shit-post.
As another anon noted, he could be sick/dying. I'm not up to date on the Brit royal family…extreme disinterest (no offense intended Britfags)
I have what seems like a logical and plausible explanation.
Trump flew in Marine 1 to meet the Queen. Because there was no motorcade, it would seem likely that British security provided the ride from Marine 1 to the Queen's residence.
Might be a nothingburger.
It did not appear to be protocol, however, Trump arrived on Marine 1, not by motorcade.
This seems like the most likely, non-conspiracy answer. But, who knows.
The tardiness might be a power move, like not bowing to the Queen.
Or, it could be the fault of the security teams.
I scanned the media for some explanation of it while I was digging on the beast. Some mention of the tardiness but no explanation.