Imagine a new, smallish, terrorist attack perpetrated by a Muslim. And imagine if, around the country, people began pouring pigs' blood on sidewalks in front of mosques.

Or imagine if someone who happened to be homosexual murdered a widely-admired actor, and then in San Francisco and New York people began publicly shredding rainbow flags in protest.

In both instances, the political Left and its media enablers justly would be apoplectic at the protesters, and would probably call for the Justice Department to charge them with hate crimes.

Not that the pigs' blood or the burned gay-pride flag actually hurt anybody physically. But the feelings of the Muslims or homosexuals would be so wounded, according to the Left, that the blood-spatterers and flag-shredders should be not just criticized but punished.

The Left would be half-right. Those forms of protest would be both mis-aimed and utterly insulting, and thus justifiably subject to bitter criticism – but not punishment. Noxious expressions in this country, unless they deliberately incite violence, are protected.

But legal protections do not insulate the protesters from criticism, nor do they make the criticism illegitimate.

Yet let the noxious expressions be aimed at the American flag or national anthem, and suddenly the Left is utterly unconcerned that the expressions enrage most Americans. Instead, the Left is full of sympathy for the protesters and disdain for those who criticize the form of their protest. Suddenly it is the "right" to protest that the Left cares about, but not whether the means or target of the protests is rightful, respectful, or appropriate.

The truth, of course, is that our wise system ensures that the expression is legally protected, and also that the equally protected blowback must come through non-governmental response, via public criticism and perhaps economic pressure. It is illegitimate to accuse the counter-protester critics as somehow trying to "deny" the protesters' "rights" when the critics aim not at their rights but at their substance or form.

NFL players can protest during the national anthem all they want – and we, most Americans, are justified in calling their protests divisive and despicable, just as we would call the pig-blood-spatterers and gay-flag-shredders odious.

The NFL players kneeling are wrong both on substance and especially on their form of protest. They are wrong on substance because this nation, as a nation, has enshrined in law every possible protection against anti-black discrimination, even discriminating in favor of blacks to make up for past injustices (e.g. affirmative action). They are wrong on substance also because the data shows their impressions about police maltreatment of blacks-because-they're-black are mistaken.

As Philippe Lemoine showed at National Review Online, "black men are less likely than white men to have contact with the police in any given year," and as the Washington Post and other databases have shown, blacks (who represent 13 percent of the population) happen to commit nearly half of all murders but amount to just 24 percent of those killed by police. (Let us rush to say this statistic says nothing about any innate black propensity to crime, as it, of course, does not take socioeconomic status or any other such variable into account.)

Yes, every time anyone, black or white, is wrongly killed by police, it's a tragedy – but there is no truth to the idea that black citizens are particularly targeted or particularly at risk by police, much less that the nation institutionally or "American society" as a whole encourages or condones such police mistreatment.

The reality is the opposite -- the substantive underpinnings for the protests are non-existent.

With those points made, let's move (partially) away from the NFL. There's a broader point, about their chosen form of protest, to be made. In college terms, let's call it Protest 101. The first rule of Protest 101 is that the right to protest contains no right to commit acts that are inherently criminal. There is no right to commit violence to make your point, no right to loot or commit property crimes, nor to deny the free-expression rights of others.

The second rule isn't legal, but a matter of manners and, frankly, of common-sense: If your protest is deliberately designed to insult the most deeply-cherished beliefs or symbols of others, you won't win others to your side – and you're also a rude lout. It is hideously rude to sprinkle pigs' blood outside of mosques or to shred a gay-pride flag, and it is hideously rude to protest during a national anthem that is a cherished expression of unity, of admirable patriotism, and of the very freedom that allows your protest in the first place.

The third rule is one of the natural human tendency towards equal-and-opposite reactions. I've written numerous times about the need for respectful dialogue and listening to the other side; yet, it must be understood that anyone who begins the conversation by deliberate insult and provocation has forfeited the right for respect. If you insult the flag and anthem that represent the cause of freedom for which millions have been wounded or killed, then you merit not sympathy but censure. An intentional, pre-planned provocation will cause a visceral reaction – and if the others' response is to verbally shred your own viscera, well, you asked for it.

The final rule of Protest 101 is this: Conduct the protest against the entity that caused the grievance. If a lunch counter won't serve you, by all means, sit at the counter. When buses discriminated against Rosa Parks, she refused to give up her bus seat. But the United States of America as an entity doesn't kill, indeed it condemns a trigger-happy cop's killing of an innocent man. Protest the killing, then, in an appropriate way, but don't denigrate the symbols of a nation of good people who would otherwise empathize with your grievance.

The same freedom that allows you to protest allows your protest to be condemned as the execrable effluvium of pampered, privileged, priapic punks, white and black alike. The condemnation would be correct.

Quin Hillyer (@QuinHillyer) is a contributor to the Washington Examiner's Beltway Confidential blog. He is a former associate editorial page editor for the Washington Examiner.

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