"Shoot to maim or cripple anyone looting," said Mayor Richard J. Daley at the time.
Now, 52 years later, President Trump has made the same threat using the military, ordering police to tear gas peaceful protesters.
"That reminded me more of '68 than anything I've seen," said Congressman Bobby Rush.
Rush said this week's events have taken him back in time. As co-founder of the Illinois Black Panthers, Rush remembers racial tension boiling over after the assassination of Dr. Martin Luther King, Jr. followed by battles with police during the Democratic National Convention a few months later.
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But the comparison is not one to one. Rush and historians say there are many differences between 1968 and this week.
"You see a multiracial group that's outside protesting right now, that's something you did not see, specifically around King's assassination," said Charles Bethea of the Chicago History Museum.
"That voice for anger is all over the place, all over the nation and world," said Rush.
Rush said similar to 1968, the anger is through the voices of peaceful protesters, not looters who he called greedy opportunists.
Despite the destruction left behind this week, Rush and historians hope the differences from 1968 will produce concrete change.
"I think now is that time, now more than ever," Bethea said. "The rest of the world is watching and participating."
Rush said now is the time, because not it may not come again. Not much changed after 1968; he said that doesn't have to be the case in 2020.