Well . . . you have to try to think of it a bit from his perspective. And this is something I didn't learn until I was much older than you, actually, when I was in Afghanistan. Beforehand, I couldn't imagine why the people there wouldn't want help, when that's what we were trying to do. It's frustrating, thinking that people you've never met, but that you personally feel a kindness towards, could not like you. But when you're there, and you see the terror and fear in everyone's eyes, about what could happen to them if we interfered. . . you understand a bit more. Not completely- I'd never want to be in their shoes, but it's a start.
It's a similar thing here, I feel. If he associates England with oppression because it's what he's always known, how does he know that you're not a part of it unless you make an effort? It can be slow, believe me, but gaining people's trust is worthwhile. I was an army doctor, and I'd go around through the villages and towns to try to help those injured after attacks from either side. Sometimes it would take weeks before some people realized I wasn't there to hurt them.
Don't take this as a personal insult- it's just the slightly messed up world we live in.