The new Muslim mayor of London, Sadiq Khan, recently warned Donald Trump not to interfere with Muslim immigration into the United States. Which raises the question: What business is it of the mayor of London whether someone is allowed into the U.S. or not? If things go badly, will he pay any price? Was he planning to immigrate here?

Unfortunately, Mr. Khan's propensity to weigh in on matters about which his opinion was not asked is the new normal in cultural discourse from the left. The very notion of not joining in whatever the liberal outrage of the day happens to be, whether it concerns them or not, never seems to cross their minds.

Leftists in Western Europe and the United States over the past half-century have refined an increasingly complex and shrill method of imposing a collectivist and/or culturally destabilizing agenda on the foundations of Western civilization. Their basic premise is that everything is their business under the guise of "justice." By couching their own personal perspective on every matter as the good and just point of view, they communicate that anyone who disagrees necessarily favors "injustice." And, of course, all "good" people should fight "injustice" wherever they find it, right?

In 1991 the Confederate Battle Flag still flew over the State Capitol near the University of South Carolina campus where I attended graduate school. The statehouse grounds were mostly serene, but occasionally busloads of protesters would come in from out of state to hold signs, yell into a bullhorn and demand that the flag be removed from above the Capitol. It always seemed odd that people would come from as far away as New York specifically for the purpose of demanding the people of South Carolina do as they ordered. When asked on occasion for my opinion, I always deferred, believing it was for the people of South Carolina to work out among themselves what flag they wanted on their statehouse.

For those around America chiming in with their opinions on the matter, it would be fair to ask "Are you black?" "Do you have plans to go to South Carolina?" The usual response is "No, but I am offended on behalf of South Carolina blacks!"

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The people of North Carolina are currently going through the same national annoyance as those in Indiana last year with their state version of the federal Religious Freedom Restoration Act. There was no liberal in America too busy to denounce Hoosiers as bigots or declare their refusal to do business with that state. The modest purpose of the law – to protect local businesses from being sued or otherwise legally harassed out of business by gay activists – was portrayed by outraged liberals as a war against homosexuals. Leftists everywhere howled in outrage. Likewise, North Carolinians are now depicted in the media as persecuting cross-dressers, all for simply codifying the previously self-evident common practice of men using only the men's toilet.

"Are you gay?" "Do you plan on purchasing a wedding cake in Indiana, need a marriage license in a particular remote county in Kentucky or plan on ever being in one of those states?" "Do you want to use the opposite sex toilet, dressing room or locker room in North Carolina?" "No, but I am offended on behalf of gays and transgenders!"

This practice never seems to work in reverse. Imagine the indignation if Christian Americans from the middle of the country stormed New York, Boston or Los Angeles and ordered liberals there to live their lives as the out-of-state conservatives demanded. Ted Cruz was savaged in New York for simply using the phrase "New York values," implying that Texans disapprove of the way New Yorkers live or comport themselves. The outrage was palpable. I wondered how many of those New Yorkers offended by having their culture and values questioned and judged by someone from out-of-state would share their opinions on North Carolina's bathroom law, abortion laws in Texas or the Confederate monuments being torn down across the South? Matters that are specifically none of their business outside the warped view of social justice theory.

It is as though liberals have mutated into creatures genetically incapable of minding their own business or living their lives without moralizing, judging and condemning Americans with traditional values.

This has been the profound cultural transformation in Western Europe and the United States. We have traversed a progression of changes from a culture with a more-or-less shared morality, through a cultural period that was essentially without a moral foundation and any choice was viewed as morally valid as any other choice, to one where the most perverted and extreme is held up as the most moral and anyone not approving and accommodating the extreme is persecuted as immoral.

To the left, it is no longer enough that American culture accepts homosexuality as a valid lifestyle option. Remember the quaint "privacy of the bedroom" argument during long-ago debates over decriminalizing sodomy? In only a generation we have transformed into a nation that requires people to participate in gay wedding ceremonies against their will under punishment of law. It is no longer enough that Americans and Western Europeans have grown so numb to the cultural changes forced by the left that virtually anything anyone does is shrugged off as just another personal choice. The new frontier for liberals is using the government to force participation in the cultural demands of the left – demands they rationalize under an arrogantly self-proclaimed banner of "justice." And that having been transformed from the common usage to mean anything liberals want at a given moment, which, in real terms, means non-stop complaining at people and forcing them to do things against their will in matters that are none of their business.

Minding one's own business was an American tradition to which we should all try to return. It would be great if someone could start a petition or a meme campaign on social media or some other effort to get everyone on the same page to Mind Your Own Business. It would be a great campaign. And maybe someone could tell the mayor of London that Americans won't tell him how to govern his city, and we would appreciate him not trying to tell Americans how to run America.

Are you sick of all the bathroom bullies? Sign WND'S petition and say NO to transgender bathroom and locker room madness!