Certainly, but Cameron also takes Sunday lunch with his kids at the Kings Head on Bledington Common and diners at adjoining tables pay them no mind. Obama can do nothing of the sort without the Secret Service commandeering the restaurant for two days in advance and setting up a command truck outside. It's less of a logistic task moving the British PM around, and frankly he is less of a target, with less of a security cordon.

Sadly, of the last ten US presidents we've had two shot, one fatally, one nearly so, plus one near-miss, so there is a near-neurotic protective instinct overshadowing his every move.