These are mobs of people refusing to cooperate and are putting peoples safety at risk. The cops acted accordingly. Refuse to disburse , and they will employ anti riot tactics. Which involve tear gas in some cities. FYI the marine wasnt targeted, he was in the crowd they shot the canister into and he happened to get hit. I bet you $1000 he wouldnt have been injured had he left like they asked them to. The video you posted where they threw the canister into the crowd was after he was already injured. And they are instructed to throw the tear gas canisters into groups who are refusing to leave and are congregating. he was doing his job. Although i think he should probably have warned them more, or thrown the canister to the side. but while i feel sorry for his injuries, HE WAS RESPONSIBLE FOR HIS ACTIONS, and unfortunatley reaped the consequences