It doesn't matter if they were warned about pepper spray two weeks, a month or a year in advance - it's still illegal
No, it's not. And you would have realized that if you'd bothered to read the non-bolded section as well as the bolded one.
The bolded section is a purposeful misrepresentation of the actual content of the policy as given directly below. The policy says "They should only be used in situations where such force reasonably appears justified and necessary.” The (obviously impartial) 'student activism' website falsely summarizes that as "University of California Police are not authorized to use pepper spray except in circumstances in which it is necessary to prevent physical injury to themselves or others." So they decided to define what is 'justified and necessary'. However the quoted text (and the actual document, which I actually read) simply state that the use of spray must appear justified and necessary to the policeman.
It's not surprising that you blindly accept several other bald-faced lies about the text of the document, including the falsehood that the police did 'nothing' to attempt to remove the protesters (they were given several eviction notices and granted many chances to voluntarily leave, then granted several opportunities to comply with the verbal instructions of the police, by definition leaving only involuntary removal and requiring physical action) and the blatant misrepresentation contained in noting that UC Police are not allowed to use physical force "except to control violent offenders or keep suspects from escaping", when the actual statement is "to subdue violence or ensure detention". In this situation the cops reasoned that, to ensure detention, using pepper spray was a better option than wrestling with the non-compliant criminals (and if they had wrestled with them and used the batons, you'd be complaining about that).
It doesn't really matter what the people in the video did a day or a week before
Nobody said anything about a day or a week before. And you still refuse to address the obvious imbalance of the situation, where a small team of campus police were entirely surrounded by a menacing group of people. You focus on the ones who stage-managed their sit-in, exactly as they expected you to. The cops were massively outnumbered by agitated people with a history of violent acts.
just look at the guy parading around with the pepper can, holding it up for everyone to see, for a good half a minute before he actually proceeds to shove it right in people's faces
That is clearly a warning. He is showing the pepper spray to the surrounding people to hopefully get them to tell the others to comply. He takes quite a bit of time warning everyone what will happen, so he won't have to use the spray. And you try to make that an indictment of him.
Now, once he uses the spray, he definitely makes sure it is sufficiently applied. Which any cop should do. Cops don't shoot to wound, either. You deploy the solution in the best manner for it to be effective. And for all your whining, notice that none of the kids move after the first blast of spray. Most don't move after the second blast. The whole point is getting them to a state of compliance, and they are being defiant. This is what they wanted to happen, so they provoked it.
In a civilized society, the offenders would be removed without being pepper sprayed.
I wholeheartedly agree! In a civilized society, these kids would have obeyed the eviction orders. In a civilized society that respected itself, that expected grown-up behavior from people who are technically adults, these kids might not have been out doing this stupid nonsense. Heck, they might have even cared enough in 2008 to want a qualified candidate for President rather than an unqualified con-man that made them feel good about themselves for voting for him. They might care about politics and economics enough to learn more than what Jon Stewart jokes about every night. They might learn too look past their own shallow selves and their own first-world problems. They might actually believe that they are inheriting a country that has worked out pretty well with some established systems and rules and ideas, rather than thinking it all needs to 'change'; or at the very least they might come up with better ideas than ones that failed and murdered millions of people last century. Society would expect them to do so and properly dismiss their activities as the self-involved stupidity of youth, rather than pretending rich kids with iPhones are the next Civil Rights movement.
The pepper spray shouldn't have been necessary. But it was. And you only have one group of people to blame for that.
The cop in the video, by the way, actually threatened to shoot the students if they don't move away
Sure he did.