I don't know if I would like Daniel Penny, him being an ex-Marine and all, but I'm convinced he did the right thing when he subdued the mentally ill guy who was acting in a threatening manner on the subway.
It's an injustice that he was ever put through a trial, but I'm glad he wasn't convicted. I was afraid the jury would do that thing where they hate to let an innocent person go completely free, so they convict him on some nonsense "lesser charge".
Heroism isn't a behavior anyone should be discouraging.
It doesn't matter what your "race" is, or whether you are closely related to the mentally ill person. This benefits YOU, too. Why act like you want aggressors running rampant, victimizing whoever they feel like? You don't want that unless you want more cops, because more cops would result, and this would just cause more problems for everyone.
Society shouldn't allow government to punish (or even arrest and try) those who step up and protect their fellow humans from those posing a credible threat. Even if the aggressor dies in the process or soon after.
Stop acting like you identify with the bad guy rather than those standing between the innocent and the bad guys unless you want the rest of us to assume you are a bad guy, too.
If you are a piece of garbage who is calling for "vigilantes" (anti-vigilantes; criminals running around committing archation, if we're being honest) to go after "white" people who aren't committing any crimes, just because of their "race", don't be surprised when this doesn't work the way you imagine. I mean, seriously!