//Harry is a Prince of the realm and therefore entitled to security payed for from this country. //
Danny,
I stand to be corrected but as far as I recall the protocol is they get Royalty Protection if on a visit to other countries, be it state,official,or private they would be entitled to Royalty Protection,courtesy of the UK tax payer. However,if they intend to take up permanent residence in L.A. then they will have to rely on LAPD's finest and his namesake 'Dirty Harry'. Providing,of course, POTUS does not snub their existance.