Eh? There's race riots in America practically every year. St Louis, Charlotte, Baltimore, Oakland, Ferguson etc.
This is far from unprecedented.

Bold take.

Yeah, not gonna happen. It's a part of the human condition. It's an 'othering' thing - 'in-groups/out-groups'. There's always gonna be a certain segment of the population that are scared/malicious/disgusted by the 'other'. Race is a fairly obvious component of personal identity and there are people that define themselves by that. As soon as they've defined themselves like that they've created their in-group. It's all identity. Identity politics and tribal lines.

In an ideal world, everyone identifies themselves as belonging to the 'human' tribe. That's likely never going to happen. The chances of everybody becoming 'enlightened' to this are so low - I don't see how it could happen. We're literally evolutionarily wired to do in/out-grouping, and I don't think everyone is capable of overcoming their basic biology (no matter how much education/tolerance-training we conduct).
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Given that (seemingly) immutable fact of life, what's the best way to express discontent with the status quo? In a way that actually accomplishes and enacts change? Rioting and property damage isn't the way. Vilifying 'ALL' cops isn't the way.

When people see stores being broken into and shit being set on fire, they think 'wow, look at all these thugs'. It doesn't enhance the message of the protestors (most of whom aren't looting shit), it lessens it. A few bad eggs taint, by association, the rest of the protestors. The bad egg analogy, with the protestors, is also the same with the police. "All cops are bad"? No, some cops are bad. Obviously, we don't want any bad eggs in policing - They are, and should, be held to a higher standard. But the fact remains, not all cops are bad - Some are bad. Just like not all protestors are predatory looters, just some. The message of the protestors is valid - As is the need for policing. When either is conducted wrongly, these base facts get wrongly questioned.

To reiterate - The looters don't represent the protestors and cops who think they're above the law don't represent the entity of policing. They reflect poorly on their respective groups, but they don't define them.

Obviously this is an emotionally charged issue, but it really does annoy me that people are so quick to pull the trigger on the other side - The battlelines are drawn and you better be on one side or the other. They want it to be so simple, one side is good and right and the other is evil and wrong. But it aint.

It's so much more nuanced than 'bleeergh, all cops are bad'. That is such a smooth brain position to hold.