Donald Trump’s resemblance to the biblical Ahasuerus was clear from the day he entered the White House, but this week he made the Book of Esther read like his reality’s pale imitation.The tweeting version of the impressionable, unpredictable and impulsive emperor of 127 realms arrived in our midst replete with a wife cast as Vashti, the queen whose job is to glamour; a daughter who plays Esther, the beautiful Jewish princess; a son-in-law who plays Mordechai the viceroy; and a revolving door through which a succession of political eunuchs, from Rex Tillerson and Steve Bannon to James Mattis and Herbert McMaster, emerge and vanish as swiftly as Harvona, Bigthan, and Teresh do in the Megillah.This week initially seemed like any other in the palace, launched with one tweet reprimanding the Federal Reserve chairman for his “horrendous lack of vision” and another charging Google with “manipulating from 2.6 to 16 million votes for Hillary Clinton,” all of which came peppered with a bid to buy Greenland.It’s been this way for three years, and the world has grown accustomed to dismissing such bizzarities as harmless entertainment. The answer to former Danish prime minister Helle Thorning-Schmidt’s question following the Greenland bid – “is this some sort of joke?” – was an emphatic “yes.”Yes, like the Megillah’s script it’s all been one long joke – until new protagonists barged into the plot and transformed it from lowbrow burlesque to Jewish tragedy.THE CONGRESSIONAL duo that sparked Trump’s wrath is indeed a pair of hypocrites he did well to expose. The two obviously seek Israel’s disappearance, and their antisemitic undertones scorn the values of the country where they achieved a political stardom that, in the Arab world that their families abandoned, is unthinkable.Ilhan Omar’s canting – that she had no idea what she was inferring when she said Israel “hypnotized” the world – was as transparent as her statement about the “Benjamins” – meaning American Jewry’s money – that fuel US support of Israel.Rashida Tlaib’s mention of dual loyalty, if even technically aimed at non-Jewish lawmakers, could only have been made with full knowledge of where that terminology comes from, and where it led.Now, in line with the era’s piling paradoxes, Trump has effectively joined their vitriol even while lambasting it, when he labeled as “disloyal” Jews who fail to join his attack on that couple.Yes, Trump has Jewish grandchildren and probably never meant to sound the way he sounded. Heaven knows the man often has no idea what he says. Still, he activated the sensors with which we Jews scan such rhetoric’s potential interpretation – and its ability to spread this fast, and run that deep.That is why, in terms of American Jewry’s future, what matters most is not what Tlaib, Omar and Trump said, but the audiences that sprawl beyond them, namely, working-class Christians and immigrant Muslims.LIKE CLASSIC antisemitism, the anti-Jewish energy our era is gathering originated in Europe, where it fused the contradictory forces of Islamism, neo-fascism, and New Leftism, all of which exploit the epoch’s economic disillusionment and social alienation.In recent years, this configuration has crossed the Atlantic.This column has long argued that the rise of Donald Trump is not the electoral accident US Democrats delude themselves that it is. Rather, it is driven by a critical mass of the population that feels socially disenfranchised, economically threatened, culturally invaded and physically insecure.The absurdity of the sense of invasion is immaterial. What matters is that this is how people in Middle America feel. Politicians like Tlaib and Omar only intensify these fears, and the poor-white fear they provoke is what Trump likely intended to fan when he attacked the two’s anti-Israeli record. Did Trump similarly intend to ingratiate the white supremacists for whom the sound of an American president pillorying “disloyal” Jews was until this week a utopian dream? I don’t think so. But for American Jews, the enigma of Trump’s intentions is now academic.What matters is that there is an angry Christian audience in the US that is vulnerable to the kind of anti-Jewish rhetoric Trump just uttered – and at the same time there is also a growing Muslim population that is vulnerable to the vehemence Omar and Tlaib trumpet from Capitol Hill.Now, with poor whites behind them and poor Muslims ahead of them, many American Jews will be tempted to veer sideways, some to the Right – to the cozy company of neoconservative WASPs – and some to the Left, to the company of anti-Israeli ultra-liberals.Once within these opposite corners, American Jews will fight the antisemites they face while also fighting each other. That is a well-tested recipe for defeat. It will mean that American Jewry has forgotten everything and learned nothing from its ancestors’ appalling failure to unite in the face of the Holocaust.Yes, we Israelis are also split in myriad ways – politically, socially, economically, religiously, culturally, you name it. However, when faced with a vicious external enemy, we unite. That is what we did on the eve of the Six Day War in 1967 and that is what we did in the face of last decade’s suicides’ war.The question to American Jewry is therefore this:Can you produce, just for one event – perhaps a march up Fifth Avenue – a united front led by, say, anti-occupation novelist Michael Chabon, pro-settler activist Mort Klein, anti-Bibi actress Natalie Portman, Republican donor Sheldon Adelson, anti-Israeli linguist Noam Chomsky, Israel advocate Alan Dershowitz, J-Street founder Jeremy Ben-Ami, Rabbi Malkiel Kotler of ultra-Orthodox flagship Lakewood Yeshiva, and Rabbi Jonathan Hecht of Reform Judaism’s Hebrew Union College?Can such a cross-section of American Jewry emerge, arms-folded, just once, just to jointly stand up to America’s antisemitic demon: If not for any other reason than simply because – much as some in that row would be so alien to each other – to that demon they are all the same?