The Western world is facing an unprecedented threat from a global eclipse of reason.Deranged falsehoods about Jews and Israel pour out of the Arab and Muslim world. Iran’s Supreme Leader, Ali Khamenei, asserts that the Jews are a “cancerous tumor.” Sunnis tell each other that the Jews are a global conspiracy of evil.Jews recognize such murderous and paranoid lunacies from the ravings of last century’s Nazis and communists and, before them, Christians in thrall to medieval and apocalyptic conspiracy theories.It would be natural to suppose that all those civilizational trauma have left the Western world sadder but wiser. Alas, that is not the case.For all their horrors, fascism and communism were confined to particular regimes, in Nazi Germany and its fascist allies or the Soviet Union and its satellites.For sure, the rest of the world remained for far too long in denial of these terrible realities. But Western society itself had not been coopted into these psychopathic creeds.Today, though, the terrifying reality is that, confronted by totalitarian forces of irrationality and malice toward the civilized world, the most powerful sectors of that very same civilized world have themselves been consumed to a greater or lesser degree by something horribly similar. The implicit premise on which the US-led deal with Iran is based is that the only way to stop the Iranian regime from getting the bomb is to enable it to get the bomb.Ludicrous? Of course. At every level, this deal is an utter farce. It is supposed to monitor Iran’s compliance through inspection and verification. Yet it has emerged that the IAEA has done side-deals with the regime which will even allow Iran to inspect and verify itself by collecting its own soil samples.The deal will delay the Iranian bomb only for 10 years, and that’s if Iran doesn’t cheat – which it has reportedly already started to do. Congress has been given intelligence evidence that, having agreed to allow IAEA inspection of its suspected nuclear military site at Parchin, the regime has brought in the bulldozers to conceal the evidence.A poll by Quinnipiac University has revealed that 58 percent of Americans believe this deal would make the world less safe. No surprise there; any rational person would surely view it as an outright capitulation to terror. Yet astoundingly, the Obama administration is blaming Israel for turning America against it.Secretary of State John Kerry has threatened that if Congress blocks the deal, Israel will be to blame. He also claimed that while Tehran has “a fundamental ideological confrontation” with the Jewish state, it has not implemented “active steps” to “wipe it off the map.”No active steps? For heaven’s sake, that’s one of the purposes of its nuclear program – which Kerry, to his eternal shame, is now helping turn into a radioactive step.Let’s be charitable: Kerry is said to be spectacularly stupid. No such explanation, though, can sanitize Obama’s outright malice toward not only Israel but the Jewish people.Railing against “well-financed” lobbyists and the “big check writers to political campaigns” for opposing the deal, Obama thus threw in the faces of American Jews both the charge of malign Jewish conspiracy and the canard of dual loyalty. Only Israel, he claimed, was against the deal (thus ignoring the passionate opposition of Saudi Arabia and large swathes of the Arab world). The only people against it, he said, were warmongers. Thus Obama managed to turn Israel from being the designated target of genocide into the sole country which actively wanted war.But Iran is targeting not just Israel but America itself. Obama actually denied this, claiming that Iran wasn’t going to aim its weapons at the United States.What, then, does he think its intercontinental ballistic missiles are for? What part of Iran’s regular chant of “Death to America, death to Israel!” doesn’t he understand? In the US, the population overwhelmingly supports Israel and understands the threat from Iran.But the president’s agenda of empowering the Arab and Muslim world translates into a vicious animus against the one country, Israel, that stands in his way.Britain presents the mirror image, with Prime Minister David Cameron sounding increasingly supportive of Israel but where the intelligentsia is consumed by virulent and irrational hatred of the Jewish state.In Britain, there has been a total absence of any discussion of the Iran deal. Instead, there has been scandalized coverage of the terrible events in Israel last week, the murderous firebombing of the Arab Dawabsha family and the Jewish terror attack on the Jerusalem Gay Pride Parade.There has been no coverage whatever of the dozens of terrorist attacks on Israeli Jews which have been going on now for months. Instead there was a BBC TV Panorama show devoted to the Jerusalem Light Rail system.This was an absolute travesty, composed of historical illiteracy, present-day distortions and wholly unrepresentative and selective interviewing. The light rail is a force for integration since it brings Israeli Arabs into central Jerusalem. Yet presenter Adam Wishart – himself a Jew – only looked in the opposite direction and portrayed it, entirely falsely, as a weapon of Israeli colonization of Arab land.The BBC dismissed complaints about the show.But it is no use whatsoever complaining to the BBC about its anti-Israel animus. The most frightening aspect of this anti-Israel ideology is the way it takes over the mind so that those in its grip are intrinsically unable to recognize their own irrationality.Accordingly, the BBC really does think that its anti-Israel position and wider knee-jerk leftism represent the political center-ground. So those who actually occupy the center-ground and who uphold truth against lies are dismissed as extreme or “rightwing” – and so cannot ever have truth on their side.Since this mind-bending left-wing prism is the default position amongst the intelligentsia in Britain and the Democratic Party in the US, Israel and its supporters are in the nightmarish situation of being the only people telling the truth about what is happening – and yet being disbelieved or smeared simply because it is they who are saying it.In the US, Israel is engaged in a desperate struggle to alert American legislators to the awful truth that their president has empowered the world’s principal terror regime and is making a nuclear war much more likely.In Britain, it finds itself up against a general culture of unreason. Much nevertheless can still be done if Israel develops a coherent strategy to combat this culture. But to do that, it has to be prepared to delegitimize the delegitimizers and hold their feet publicly to the fire – even when they are ostensible allies.And that will take a shift of perception that Israel has not yet quite made.Melanie Phillips is a columnist for The Times (UK).