I don’t know if you’re being willfully dishonest or you’re genuinely oblivious.
EDIT: also Renee Good’s killing is a domestic issue and is much closer to home for most Americans than Iran. It is not surprising that there is a lot of chatter about it.
I think the problem might be that taking personal responsibility for one's own morality and beliefs is a burden that's too much, too scary, for many people.
It feels a lot safer and more comfortable to simply look around you and draw your morals from what everyone else is saying and doing.
There's something isolating about trying to be good.