No country that's ever held any modicum of power or reverence is free of guilt... Canada has its own skeletons in its closet, just the same as any major country. The key difference is Britain has been around as a cohesive whole for far, far longer than many countries out there so of course it's going to have a long list of historical faux pas.
Nobody is safe from finger pointing... Germany, France, America, Italy, Russia, Canada... it's not fair to pick on one and not recognize the idiocy of the others.