Turning the other cheek is fine, when it's your own cheek. When someone else is being abused, it's time for an intervention.
Of course, it's quite possible that President Obama does not recognize abuse when he sees it, because he himself was so well protected by his maternal family. Picking himself up and dusting himself off is a good response to the random bully. It's totally inadequate when deprivation and denigration are the order of the day.
Deprivation of rights is the essence of crime. It involves the taking of something to which the deprivator is not entitled, unless society imposes the deprivation as punishment -- in revenge, so to speak, for an earlier unwarranted act.
We generally presume that the criminal wants what he's taking. So, for the most part, deprivation boils down to theft. Which makes it hard to account for why a wealthy person would, and often does, perpetrate crime. Even more puzzling is why some people seek to deprive others of things they don't even want for themselves (e.g. school lunches for little children and doctoring for their moms).
The answer, I suspect is jealousy. Jealousy is what we refer to as envy when we enumerate the "seven deadly sins":
wrath
greed
gluttony
pride
lust
sloth
envy
Obviously arising from the basic instinct to survive that, in some people has gone awry, the sins aren't so much "deadly" because they kill, but because they are, ultimately self-defeating. Indeed, sloth probably acts as a restraint -- the saving grace that tempers behavior just enough so the sinner escapes being killed in revenge.
Why envy persists in the genome is less clear. What purpose does it serve in its moderated form, to promote individual survival as do the desires for nutrition (greed, gluttony) and social connection (lust)? The answer, I suspect, is emulation. That is, envy is an exaggeration of the instinct to copy the behavior of others and thereby acquire the necessities of life. And, frustrated either by a lack of skills or rejected desire, envy (jealousy) turns into wrath.
The story of Cain and Abel actually tells us that. Because Abel had found favor with God, emulating the creation of good things to eat out of the earth by planting, jealousy drove Cain to kill Abel, depriving him of life, even as Cain could deny knowledge of his reckless deed, since it gained him nothing.
In the 21st Century, it's people who consider themselves conservatives, too cowardly to kill outright, who aim to deprive poor people of the necessities of life -- jealous because the poor are still blessed and progressives share their love. Envy is what drives these descendants of Cain and leaves them as clueless now as he was in the beginning.
"Am I my brother's keeper?" Indeed. What a question!