With world stock markets plummeting and unemployment spiking, it is only prudent to ask: will the global economic meltdown provide the toxic fuel for haters?

Early signs from Europe are far from reassuring. Ed Balls, a UK cabinet minister, worried that fascist movements, subdued since the 1930s, could emerge as a powerful force in British politics for "the next year, the next five years, the next 10 and even the next 15 years". Derek Simpson, joint general secretary of Unite, a UK trade union, warned that the xenophobic British National party was leveraging the slogan "British jobs for British workers" to infiltrate the labour movement.

A poll commissioned by the AntiDefamation League reveals that old habits die hard in Europe. Jews are the scapegoat du jour for nearly a third of Europeans. About 40 per cent of respondents - including more than half the Hungarians, Poles and Spaniards - said Jews had too much power in business. In Spain, 74 per cent said it was "probably true" that Jews had too much control over financial markets.

A BBC poll indicates little sympathy for Israel among today's Germans - only 9 per cent view Israel as "mainly positive", while 65 per cent see it as "mainly negative". These numbers are matched by anti-Jewish violence, attacks on synagogues and intimidation of Jews on the streets of Europe.

Meanwhile, the historic roots of European anti-Semitism were exploited during the recent Gaza war by Hamas apologists linking alleged Israeli crimes against the Palestinians to the fictitious Jewish conspiracy to dominate global economic and political power. Fawzi Barhoum, a Hamas spokesman, blamed the war on "the Jewish lobby that put the US banking and financial sector into place" and "controls the US elections and defines the foreign policy". Echoes of Hamas's hatred carried over to top North American campuses, where websites equate Israelis with Nazis and Gaza with Auschwitz.

In the internet world, financial blogs and chat rooms also characterise the Lehman Brothers collapse as the latest chapter in age-old Jewish financial conspiracies. The same propagandists now fantasise that Israeli banks received $400bn (€318bn, £281bn) from Lehman executives ahead of its collapse. Never mind that the top targets of Bernard Madoff's alleged $50bn fraud were primarily fellow Jewish individuals and institutions - anti-Semitic conspiracy theorists credit him with being a major cause of 10m newly unemployed Chinese returning to the countryside.

Fortunately, the latest conspiracy crackpots remain marginalised in a society that has just elected its first African-American president. Yet history cautions that the US in times of crisis enjoys no immunity from powerful hate movements. The panic of 1837 triggered the first global depression, lasting seven years. While the Bank of the United States was blamed by many for that crisis, Alexander McNutt, governor of Mississippi, labelled English banker James Rothschild a blood brother of "Judas and Shylock". Then, the first wave of "Famine Irish" immigrants were greeted by "No Irish Need Apply" campaigns, claiming they stole jobs and wereloyal only to the Pope.

Subsequent crises spawned their own scapegoats, but the Great Depression looms largest in our nation's psyche. Despite the masses of Jews in breadlines, "Radio Priest" Father Charles Coughlin won a national following by equating "Jew" with "international banker". Recently, historian Alan Brinkley suggested Louisiana politician Huey Long's "Share Our Wealth" crusade, linked after his death to Fr Coughlin, may become a model for "economic populist" movements targeting the sins of Wall Street.

Today's European anti-Semitism is eerily similar to that shown by a 1938 poll revealing that 50 per cent of Americans had a low opinion of Jews; 45 per cent thought they were less honest than Gentiles in business; 24 per cent thought they held too many government jobs; and 35 per cent believed that Jews were largely responsible for their own oppression in Europe.

"Can't happen here"? If our economic woes are not reversed, old hatreds will be reformulated for the internet age to scapegoat Latinos and other minority groups for job losses, Jews or the financial meltdown, Arabs and Asians for currency manipulations, and the list goes on. Americans must be on our guard or we could lose something more precious than our shrinking pensions.

Rabbi Abraham Cooper is associate dean of the Simon Wiesenthal Center. Harold Brackman, a historian, is a consultant to the Simon Wiesenthal Center

Copyright The Financial Times Limited 2009

Financial turmoil evokes familiar scapegoats