See the problem with this is most people commenting have watched to many films and never been in situations like this themselves, they have seen and read lots of things like this and feel like they know how they would react and what should have happened but the reality is when places in said situations how you actually react is entirely different to how you think you would regardless of training.Full control?
The whole episode lasts about what? 5 to 8 seconds? How could they be in full control in that short space of time when he has been cracked a couple of times and knocked to the ground and witnessed his colleagues facing similar attacks.
As someone else said, at that exact moment it was a case of survival and use of force "by any means necessary".