Since Oct. 7, 2023, we have been lectured nonstop about the supposedly singular sins of Israel.

The campuses, the left-wing media and Democratic socialist officials, following the cue of student activists and leftist professors, have painted Israel and its Jewish supporters as Nazis, fascists and among the worst murderers in today’s bloody world.

This is nonsensical.

The medieval-style massacre of 1,200 Jews in their homes on Oct. 7, during a time of peace, should have increased awareness of the existential dangers Israel faced.

Instead, it spawned a storm of antisemitism.

The libels of genocide and ethnic cleansing being cast at the Jewish state apply far more accurately to a host of other nations.

Over the decades, we have sold arms and given billions of dollars in military aid to Turkey — yet between 1915 and 1920, the Turkish government conducted a genocidal policy of ethnic cleansing against its Armenian population, for which it has never apologized and which it continues to deny.

None of the current critics of Israel seems worried that Turkey invaded Cyprus in 1974 and ethnically cleansed Northern Cyprus of its Greek inhabitants.

There are no demonstrations anywhere in America on behalf of the far more recent “Nakba” of the Cypriot Greeks.

Did Columbia University activist Mahmoud Khalil ever rally his armies of idealists to damn the Islamic-driven ethnic cleansing of the ancient population of Christian Armenians, or to call for the United States to sever its joint arms deals with Turkey?

Before the 1967 war, nearly 1 million Jews were living in the Arab and Muslim Middle East, descendants of those who had been there for centuries.

But during the serial Arab-Israeli wars of the 20th century, they were almost entirely pushed out of those countries.

None appear today before television cameras, shaking the keys of their confiscated homes in Algiers, Amman, Baghdad or Cairo.

Of course, no one dares to say Arabs “ethnically cleansed” almost all their Jewish citizens.

Between 1987 and 1989, the Somali Marxist dictator Mohamed Siad Barre began slaughtering entire rival Somali clans. The eventual death toll may have reached nearly 200,000.

When Barre’s murderous regime finally imploded, thousands of Somali refugees who had either supported him or belonged to his clan fled to the once-despised West, especially the United States and Europe.

Among those pro-Barre refugees were apparently members of Rep. Ilhan Omar’s family, including her father, a colonel and regimental commander in Barre’s army.

It’s a bitter irony that Omar is now such a sharp critic of Israel and the United States, given that America granted refuge to her family.

Yet we are not aware that any Somalis today are being accosted by strangers — as Jews are — and lectured about what their former leader’s regime did to those thousands of innocent civilians.

After Oct. 7, we were also lectured that Israel was not just guilty of various war crimes, but illegitimate in its very existence.

Indeed, it became chic to condemn Israeli Jews as “settler colonialists” — despite residing in the 3,500-year homeland of the Jewish people.

New York Mayor Zohran Mamdani, an immigrant from Uganda with family roots in India, is one such critic.

But under those very reductionist left-wing definitions, should not the Indian community in Uganda — which makes up at most a wealthy 1% of the population — be defined as settler-colonialists (in addition to suspect rich one-percenters)?

The wealthiest man in Uganda is an Indian-Ugandan billionaire, and the minuscule Indian population there today exercises power and influence disproportionate to its numbers — in stark contrast to the impoverished indigenous population.

The Mamdani family certainly is not representative, in terms of money and status, of the average Ugandan.

Should not Mamdani himself, born in Uganda among “settler colonial” exploiters, have to defend himself as a son of “interlopers,” as is often said of the Jews in Israel?

The list of these absurd asymmetries could be expanded endlessly: The furor over Gaza is accompanied by the silence over the more than 30,000 unarmed Iranians recently murdered by a theocratic dictatorship, one often cheered on by the left for its resistance to the United States.

Or the disgraceful and mostly covered-up history of France in Chad, where French repressive measures over the course of their 20th-century colonial occupation led to as many as 300,000 deaths.

In short, the telltale sign of antisemitism is not necessarily opposition to Israel.

It is instead an endless fixation on Israel’s supposed “crimes,” when far greater documented horrors elsewhere never merit a word.

Victor Davis Hanson is a distinguished fellow of the Center for American Greatness.