What Hamas did cannot be excused. Why are so many on the left trying to do so anyway?

The massacre of more than a thousand innocents in Israel by Hamas has reignited a smoldering conflict. The reactions to that terrorist attack — and to Israel’s response to it — have also exposed a divide in American society that, for most, had been purely academic.

Plenty of Americans feel some sympathy for the two million residents of the Gaza Strip. But most who have avoided the theoretical debates of college campuses were shocked at the hand-waving, equivocating, and even outright approval shown by some for the Oct. 7 carnage.

Hamas struck at civilian targets — killing men, women, children, and even babies — raping, kidnapping, and murdering them. The gruesome acts were a sadistic spree of violence, nothing that could be recognized as “resistance” or a “fight for freedom.”

It is hard to comprehend how anyone could look at the atrocities Hamas committed there and equivocate or try to justify them in the least. Acts this horrible are completely out of bounds, no matter who commits them or why.

Yet before the Israeli bodies were even counted, let alone buried, campus radicals were placing blame squarely on the victims. A soon-to-be infamous letter was circulated from 36 Harvard student groups that said the orgy of violence was Israel’s fault, not Hamas’.

» READ MORE: America’s challenges are complex and serious. Too many of our leaders aren’t. | Kyle Sammin

“The apartheid regime is the only one to blame,” the letter’s signatories proclaimed. “Israeli violence has structured every aspect of Palestinian existence for 75 years. From systematized land seizures to routine air strikes, arbitrary detentions to military checkpoints, and enforced family separations to targeted killings, Palestinians have been forced to live in a state of death, both slow and sudden.”

Without even a pause at the murder of babies, the authors called for “a firm stand against colonial retaliation.” After the backlash forced real-life consequences into some of the activists’ fantasy of resistance, the letter all but disappeared.

It was not an isolated incident.

Black Lives Matter’s Chicago chapter posted an image of a paraglider and a Palestinian flag — an unmistakable reference to the terrorists who entered Israel by such means. There was no line drawn between Hamas and the Palestinian people. This was full-throated support for both, and all the innocent blood Hamas had shed. That too was deleted, but the follow-up message that Gazans should “do what they must to live free” amounts to the same thing.

In formal letters, graphic designs, and marches in the streets, this was a calm, methodical endorsement of murder.

To people who view the world through the lens of the liberal Enlightenment, it is unthinkable. Something wrong is always wrong, no matter who does it. Rules about right and wrong, consistently and neutrally applied to all individuals, is the American way of thinking about things, and appeals to basic human ideals of fairness. The idea that the same rules apply to everybody has led to the greatest advances in equality and justice.

“As I would not be a slave, so I would not be a master,” Abraham Lincoln once said. And this concept — this democratic version of the Golden Rule — is what has led us, often through difficulty, to move forward in applying our ideals equally to all people, more and more so from Lincoln’s day until our own.

But that is not the way Hamas’ Western apologists see the world.

In the new social justice calculus, instead of dividing individuals and their actions into right and wrong, they divide all groups into “oppressor” and “oppressed.” Siding with the oppressor is bad, siding with the oppressed is good — and what is acceptable from one side is not acceptable from the other. Absolute principles of right and wrong, in this worldview, are one way those in charge wield power.

A person who sees the world this way is required to look at the actor before determining the rightness of an act. Because these people view Israelis as “oppressors,” the acts of the “oppressed” are never questioned.

It sounds new, but it is merely a remix of the pre-Enlightenment world, where people would confidently proclaim that their tribe was right, yours was wrong, and never attempt to reconcile the double standard. Approval came from who you were, not what you did. Old-fashioned tribalism and new-fashioned “anti-racism” both see groups first, individuals second — if at all.

This oppressor/oppressed dynamic uses the word colonialism. Anti-colonialism in the 1940s and ‘50s was a simple concept: The European empires should grant independence to the captive nations of Africa, Asia, and elsewhere in the world. That happened. But now we hear the same epithet of “colonial” applied to nearly any powerful nation in increasingly strained definitions.

Israel is called colonial even though Jews have lived in the region for millennia. Arabs, who conquered the region from the Roman Empire in the seventh century, are not colonialists, somehow. But again, there is no universal principle for determining who is or isn’t colonizing, and there hardly could be in a world that has seen thousands of years of migrations, wars, and conquest.

» READ MORE: New Mexico’s ban on carrying guns in public is yet another threat to the rule of law | Kyle Sammin

It should not come as a surprise that removing consistent, equal, neutral principles leads back to pure tribalism. It is also not a coincidence that the new tribalism, like the old antisemitism, singles out Jews for abuse. “From the river to the sea, Palestine will be free” is an open call for the elimination of the Jewish state.

Before the events of Oct. 7, rhetoric about “decolonization” could be dismissed as academic posturing. Radical chic is nothing new. But ideas matter, and they spread. After Oct. 7, there is no hiding the blood implied in those words.

The rhetoric of “decolonization” becomes a progressive cloak for genocide.

Convinced of their righteousness, the post-liberal left will openly say what was once unspeakable. They are emboldened to hate because they think that actions on behalf of the “oppressed” cannot be wrong, no matter how hateful. Consider the widespread incidents of posters of the Israeli hostages being ripped down: How could anyone fail to sympathize with people — including little children — held captive by terrorists? But they do when any criticism of an “oppressed” group is forbidden.

Take away the theory and the esoteric vocabulary, and it’s just the same old bigotry. Old wine in new bottles, a brand refresh for the digital age. At its heart, it’s the same way of thinking that has driven bloodshed and division since humanity’s earliest days.

Our retreat from Enlightenment ideals is not progress — it’s a return to tribalism and hate.