I thought this would be an interesting question to tackle, because my perspective on it is probably a little weird. I've said that I don't like sitting on the fence regarding questions like this because its 'easy'. When asking whether humans are better at creation or destruction, its lazy to just say "Both" and move on with your day. Saying 'both' doesn't provide any insight to the question or what its trying to get you to think about, so I'd make the stand that people really sit on the fence with stuff like this simply to avoid thinking about it. I hate politics, and I don't know which party I fall under or whether I'm conservative or liberal, but I know if I did research on everything and thought about it, I wouldn't be undecided. I simply don't know enough to be able to say one way or another where my opinions put me.
Anyway, back to the question, I think everybody should have the personal right to achieve happiness, but only the people that deserve it will actually find it. Nobody should be denied the chance to be happy, but I think its an elusive thing, and people look for it in the wrong places. I think we spend a lot of time pretending to be happy and not really looking for it, and those people who are hateful and make poor choices are simply those who don't deserve to be happy. I don't think there is some magical barrier that prevents wrongdoers from being happy, but rather I think people who make bad decisions are kept from happiness by themselves and the choices they've made. People that try to reconcile their actions instead of atoning for them are lying to themselves, and it could be the thing that makes them resentful.
If I'm not happy, it obviously means that I don't like the state of my life. At the same time, though, it could also mean that I'm headed in the wrong direction. Maybe the happiness I'm pursuing isn't what I think it is, and I need to reevaluate what it is I'm really looking for and where my path will lead.
So, it may be cheating to say that we both have a right to be happy and have to earn it, but I really think that's how the world works. We as a society have a moral obligation to ensure that everybody gets to live the way they want to, but at the same time, I think happiness is something that must be earned by the individual. We all have to work for our happiness, and just because its a possibility doesn't mean its easy to find. I think many of us are given the opportunity to hit that target and be content with our lives. The only thing that's stopping us is poor aim, and sometimes I think most of us are blindfolded, too.