Pragmatically, one shouldn't argue with a group of armed men that presumably are acting within the scope of the law. It too often results in tragedy, as demonstrated in the video clip.
I don't entirely agree with either Steveh or Freeman in their respective assessments that are entirely based entirely upon the story synopsis and video clip. Though there are some points of their arguments that I do agree.
It boils down to the question of a reasonable standard utilized by the police officers take this man into custody. Given the terrain, numbers of active LE on location, and the weaponry possessed by both sides, etc, there certainly is enough room to further examine the matter. Additionally, while the police don't have a duty to retreat, they do in fact have a duty to exercise the aforementioned reasonable standard in keeping with Graham v. O'Conner and Tennessee v. Garner.
Would I have utilized a flash-bang grenade to prevent him from leaving? No.
Would I have shot the man, given the terrain and distance from the man? No again.
Would I have arrested him for trespass, after his refusal to leave? Yes.
Would I have had to arrest him right then and right there? No.
Could I have bided my time and catch him in a more desirable location? Yes.
Very good points, all of them. Not sure if that part has really been discussed; the part about why they needed to immediately take the guy into custody. Yes, maybe he did or had threatened people, but the only ones that were actually threatened at the time were the trained officers who did have the option to not get close enough to be in the imminent danger that they found themselves in.