Two months ago, a petition bearing more than 110,000 signatures was delivered to The Post, demanding a ban on any article questioning global warming. The petition arrived the day before publication of my column, which consisted of precisely that heresy.

The column ran as usual. But I was gratified by the show of intolerance because it perfectly illustrated my argument that the left is entering a new phase of ideological agitation — no longer trying to win the debate but stopping debate altogether, banishing from public discourse any and all opposition.

The proper word for that attitude is totalitarian. It declares certain controversies over and visits serious consequences — from social ostracism to vocational defenestration — upon those who refuse to be silenced.

Sometimes the word comes from on high, as when the president of the United States declares the science of global warming to be “settled.” Anyone who disagrees is then branded “anti-science.” And better still, a “denier” — a brilliantly chosen calumny meant to impute to the climate skeptic the opprobrium normally reserved for the hatemongers and crackpots who deny the Holocaust.

Then last week, another outbreak. The newest closing of the leftist mind is on gay marriage. Just as the science of global warming is settled, so, it seems, are the moral and philosophical merits of gay marriage.

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To oppose it is nothing but bigotry, akin to racism. Opponents are to be similarly marginalized and shunned, destroyed personally and professionally.

Like the CEO of Mozilla who resigned under pressure just 10 days into his job when it was disclosed that six years earlier he had donated to California’s Proposition 8, which defined marriage as between a man and a woman.

But why stop with Brendan Eich, the victim of this high-tech lynching? Prop 8 passed by half a million votes. Six million Californians joined Eich in the crime of “privileging” traditional marriage. So did Barack Obama. In that same year, he declared that his Christian beliefs made him oppose gay marriage.

Yet under the new dispensation, this is outright bigotry. By that logic, the man whom the left so ecstatically carried to the White House in 2008 was equally a bigot.

The whole thing is so stupid as to be unworthy of exegesis. There is no logic. What’s at play is sheer ideological prejudice — and the enforcement of the new totalitarian norm that declares, unilaterally, certain issues to be closed.

Closed to debate. Open only to intimidated acquiescence.

To this magic circle of forced conformity, the left would like to add certain other policies, resistance to which is deemed a “war on women.” It’s a colorful synonym for sexism. Leveling the charge is a crude way to cut off debate.

Thus, to oppose late-term abortion is to make war on women’s “reproductive health.” Similarly, to question Obamacare’s mandate of free contraception for all.

Some oppose the regulation because of its impingement on the free exercise of religion. Others on the simpler (nontheological) grounds of a skewed hierarchy of values. Under the new law, everything is covered, but a few choice things are given away free. To what does contraception owe its exalted status? Why should it rank above, say, antibiotics for a sick child, for which that same mother must co-pay?

Say that, however, and you are accused of denying women “access to contraception.”

Or try objecting to the new so-called Paycheck Fairness Act for women, which is little more than a full-employment act for trial lawyers. Sex discrimination is already illegal. What these new laws do is relieve the plaintiffs of proving intentional discrimination. To bring suit, they need only to show that women make less in that workplace .

Like the White House, where women make 88 cents to the men’s dollar?

That’s called “disparate impact.” Does anyone really think Obama consciously discriminates against female employees, rather than the disparity being a reflection of experience, work history, etc.? But just to raise such questions is to betray heretical tendencies.

The good news is that the “war on women” charge is mostly cynicism, fodder for campaign-year demagoguery. But the trend is growing. Oppose the current consensus and you’re a denier, a bigot, a homophobe, a sexist, an enemy of the people.

Long a staple of academia, the totalitarian impulse is spreading. What to do? Defend the dissenters, even if — perhaps, especially if — you disagree with their policy. It is — it was? — the American way.

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