I'm sorry to hear what happened to the people in the pulse shooting. It is not justified to use violence against anyone who has not initiated violence towards you.  That being said I understand why the authorities would want to ban people who practice risky lifestyles from donating blood.  The last thing we want is to have a blood supply that's contaminated with diseases because of the practices of people who engage in risky lifestyle choices and also sinful ones as well.  No violence should never be the answer to people no matter what their lifestyle, But one should never condone something that is bad for society in the long run.