How to "toughen" up my kid?

My son is 11 years old now and I love him more than anything. He's the reason I work as hard as I do. I was in prison for the first year and a half of his life and since I came out I've been working almost 12 hours a day everyday just to make sure his life is nothing like the one I had when I was his age.My wife's uncle (who is quite wealthy) very kindly allowed my wife and son to stay in one of his spare houses and since my release I've been living here with them as well. It's a very nice neighbourhood just outside of London and has excellent schools and extracurricular activities for my son.He's a very sporty and active kid like I was. He plays football, basketball, rugby and takes part in all the athletics competitions at school. Watching him grow up and be happy makes me happy but I do have a slight concern.My son got into a fight at school recently. Me and my wife were called in and found that my son had a bloody nose and a black eye. There's a bully at the school who attacked him and he couldn't defend himself.Growing up I got into a lot of fights at school, it was a rough school in a rough area. My mistake was assuming that I could shelter him from the kind of stuff I had to deal with as a kid. I realised that sheltering him has made him a bit soft. I know not every kid is supposed to fight and be aggressive and I'm happy that he doesn't get himself into trouble but seeing him after he got beat up by the bully just shattered my heart and I couldn't help but feel partially responsible for not teaching him how to defend himself.I've suggested to my wife that he take up some form of martial arts or something like boxing but she disagrees and my son doesn't seem interested in that kind of thing at all when I mention it. I was just wondering outside of taking up martial arts is there anyway I could "toughen" up my son? Not just physically, I want to make sure he can defend himself in a fight but also mentally as I'm aware of how children these days especially teens and pre-teens are not as mentally strong as they were before the social media era.Has anyone been in a similar situation? Do you recommend I make my son take a few fight classes even if he does not want to? I want him to be himself and happy but I want to make sure he's already prepared for how tough the world can be. Thank you in advance for any help. via /r/Parenting https://ift.tt/35qjOCq