trisher
I think the problem is that some can't see the difference between having a private life where you decide exactly when and where you will make things public, and having a life where you are organised and supervised by other people who decide what will be public and you are just expected to go along with things.
Most of the members of the royal family organise their own security, unless they are going about official royal business. Harry is not going about royal business, and he himself has chosen not to be a part of the royal firm so he is visiting this country as a private individual
At major public events involving the Queen, there will be a strong armed police presence, which won't differentiate between a threat to Her M and a threat to any of the others present (including Harry and his family) bcause a threat to one present is a threat to Her M and all the rest.
If he wants the privilege of armed police protection granted to royal representatives, he has to take on the responsibility of representing the Queen at public events. He doesn't want to do that.