The takedown was not justified. He was complying to not face the officer, but the officer had already decided to take him down. He reacted, as anybody would who's about to be thrown to the ground. If there's any justice, the real charges are going to get dismissed if he gets a public defender who's the least bit interested and not going to go for a plea bargain, and not before he spends the next year locked up in remand until the the case gets to trial.
The US is the exceptional society. Uniforms can violate people's rights, but that's ok and 'thanks for your service'. Employees of the US government can shoot people abroad and they call that 'collateral damage'. The public mental shift started with the movie Saving Private Ryan, as US servicemen are seen shooting enemy soldiers who had surrendered, and that's ok because they were bad guys (they did a lot of that during WW2, but it was never acknowledged because they won the war; the losers though had to account because they lost; now, it happens so often that nobody cares, especially if the shootees are brown and have odd looking headdress). Now, the war has reached the homeland, and police are militarized, and the military have enemies. Black people are automatic suspects, and the innocent will be classed as collateral damage. Nobody cares unless it happens to them.