A half-century ago today, Sirhan Sirhan murdered the senator and presidential candidate Robert Kennedy. It is often forgotten, writes Warren Kozak, that the assassination had more in common with the attacks on the World Trade Center of 1993 and 2001 than with the other political assassinations of the era:

Because the assassination came just over four years after his brother President John F. Kennedy was murdered in Dallas, and just two months after Martin Luther King, Jr. was gunned down in Memphis, the nation focused on gun violence and hatred of the Kennedy family in its aftermath. Many blamed right-wing racists, since the Kennedys had supported the civil-rights movement. . . . I remember the most common phrase: “They killed another Kennedy.” The “they” was generic. It wasn’t an individual; it referred to a supposed violent streak that ran through American culture and mythology all the way back to our frontier days.

But a single individual killed Kennedy, for very specific reasons. Sirhan was obsessed with both Israel and Jews. He was born in British Mandatory Palestine in 1944 and emigrated to the United States in 1956, attending school in Los Angeles. Yet even though the California economy of the 1950s and 1960s was one of the strongest in the world, Sirhan never took advantage of what surrounded him: he worked as a stable boy and never became a U.S. citizen.

The shooting took place on the one-year anniversary of Israel’s victory in the Six-Day War. This was no coincidence. When Kennedy was twenty-two-years old, he traveled to Palestine, writing articles for the Boston Post about his admiration for the country’s Jewish inhabitants. As a senator from New York, Kennedy continued his strong support of Israel. Shortly before the assassination, in a televised debate with his chief Democratic rival, the Minnesota senator Eugene McCarthy, Kennedy said he supported the sale of fighter jets to Israel.

Indeed, Kennedy was a consistent and staunch supporter of Israel—which infuriated Sirhan. In a 1989 interview with David Frost, Sirhan said: “My only connection with Robert Kennedy was his sole support of Israel and his deliberate attempt to send those 50 bombers to Israel, obviously to do harm to the Palestinians.”

Two extraordinary events demonstrate something important about Israel’s most fervent adversaries. One was a speech given at something called The People’s Forum (funded generously by Goldman Sachs), which stated, “When the state of Israel is finally destroyed and erased from history, that will be the single most important blow we can give to destroying capitalism and imperialism.”

The suggestion that this tiny state is the linchpin of a global, centuries-old phenomenon like capitalism goes well beyond anything resembling rational criticism. Even if Israel were guilty of genocide, apartheid, and oppression—which of course it is not—it would not follow that its destruction would help end capitalism or imperialism.

The other was an anti-Israel protest that took place in front of New York City’s Memorial Sloan Kettering Cancer Center, deemed “complicit” in Israel’s evils. At organizers’ urging, participants shouted their slogans at kids in the cancer ward, who were watching from the windows. Given Hamas’s indifference toward the lives of Gazan children, such callousness toward non-Palestinian children from Hamas’s Western allies shouldn’t be surprising. The protest—like the abovementioned speech—deliberately conveyed the message that Israel is the ultimate evil and its destruction the ultimate good, cancer patients be damned.

The fact that Israel’s adversaries are almost comically perverse does not mean that they can be dismissed. If its allies fail to understand the obsessive and irrational hatred that it faces, they cannot effectively help it defend itself.