When Egypt and Syria attacked the Jewish state in 1973, the Conservative British prime minister Edward Heath imposed a complete ban on sales of arms or munitions to both sides, claiming this to be a policy of “evenhandedness.” Heath did so, writes Robert Philpot, in part to avoid breaking ranks with the European Economic Community, which the UK had just joined under his leadership. And there were other reasons as well:

Fearing that an interruption in supplies would deal a further blow to his already teetering economic policy, Heath sought to appease the oil-producing Arab states. . . . Refusing to condemn aggression perpetrated against Israel, . . . Britain urged a cease-fire and a return to the 1967 frontiers and . . . refused to allow the U.S. to resupply Israel from British bases (thus ruling out Cyprus) and placed restrictions on flights out of UK installations by the Americans’ state-of-the-art Blackbird reconnaissance aircraft, restrictions that, historians believe, placed U.S. planes at great risk.

Although presented as affecting both sides, in reality the arms embargo hit Israel hardest. Perhaps the most shameful decision was Britain’s refusal to supply Israel with spare parts for weapons, including shells for Centurion tanks, that it had previously sold to the Jewish state. . . . All the while, Egyptian pilots were continuing to be trained by Britain. The opera-loving Heath appears not to have taken the risk to Israel with much seriousness, [quipping] that “the only warlike Egyptians I have ever heard of were in Aida.”

Heath met staunch opposition from within his own cabinet, including from his rival-to-be, Margaret Thatcher:

In the cabinet, the dissenting ministers . . . made the case that, strategically and morally, Britain was taking the wrong approach. . . . It was not in Britain’s national interests to see Israel’s “power to resist” weakened and the Arab countries, “which were Soviet clients,” strengthened. If Britain was willing to sell arms in times of peace and contracted to supply spare parts in ammunition, “we were in honor committed to continue that supply if war broke out.” There was “no justification,” the ministers argued, for the Arabs’ breach of the ceasefire and it was “wrong that we should appear to be tolerant of it.”

But Heath was persuaded neither by these arguments nor by the suggestion that his position was politically unpopular, a claim he attributed to “a Jewish-inspired press campaign.” Philpot argues that this was a miscalculation.

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.