What's happening in Missouri and in NYC aren't the same. What MLK had to go through, as a black man during that time, is completely different than the events that caused the Ferguson riots.
Now, I'm not saying we live in a Utopia where all races' hands are joined. But back then, blacks were seen as an inferior species, their rights reflected that. They were protesting for the human right to vote and to be seen as equal.
What's happening today, while I'm not saying race isn't a factor, is blurred along the "is it race or economic standing" line. If MLK was alive today, he'd be a politician, a governor, a highly successful and respected man. Back then? We already know, he wasn't even an equal.
Racism exists today, no doubt. But the days of accepted hatred and violence against a group of people, simply because of the color of their skin, is a thing of the past. Today, racism is systematic (yes, I know, the result of the systems and institutions being run by people with largely unconscious biases),it's subconscious, it's the white guy wondering why affirmative action is fair, wondering why it's so hard to get your shit together, go to college and get out of the ghetto.
None of it is ok, but what MLK was going against was outright brutality and hatred, which was widely accepted and many thought was ok. What we're fighting now is much less harmful, unfortunately it's also much less obvious (making it more difficult).
Today, unfortunately, there seems to be too much finger pointing, ostracizing and ignorance, from ALL parties, to get much done. We disregard the impoverished black community and write them off as lazy, we ostracize the person who asks questions that aren't PC, one side yells "RACE", while the other yells "SOCIO-ECONOMIC STANDING". MLK gave everyone this voice, he's the symbol of having your voice heard and we should all thank him.
The problem is, we are all yelling to have our voice heard, no one is listening to what the other is saying.