Niggas off the chain, because they affected
This is about the mind-state of niggas during this chaotic time period. Their mindset had been nurtured by years of neglect as suggested in the beginning of the rhyme.
This is why they went about looting and stealing during the chaos and were basically depicted to be savages by the mainstream media. Jay is simply saying that there is a reasoning behind why niggas acted that way(justified or not). This continues the theme of cause and effect.
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