You know leading Jewish Democrats are struggling to convince voters President Barack Obama is good for Israel when Alan Dershowitz has to publish an endorsement of Obama not once, but twice in the Jerusalem Post–and has to lead the endorsement by scaring voters into believing Mitt Romney will “Christianize” America.

The first endorsement appeared in August, followed by a rebuttal a few days later. Now Dershowitz has tried again, and the emphasis is no longer on Israel alone but on other issues as well. The argument for Obama, Dershowitz says, includes judicial appointments (i.e. liberal, pro-choice justices) and applause for Obama’s economic policies, which he says are leading the U.S. to out-perform other economies. But he goes further:

Republican candidate Mitt Romney has said that he would fill the Supreme Court vacancies with justices like Scalia, Alito and Thomas. A court with such a right wing majority will change America for the worse. It will dismantle the wall of separation between church and state and embolden those who seek to Christianize America. It will eliminate a woman’s right to chose abortion and will set back the trend toward equality for all Americans regardless of sexual orientation. It will continue to strike down progressive legislation, such as gun control, campaign reform and laws protecting the rights of minorities. (Emphasis added)

The argument is not worthy of rebuttal. It is a dog whistle to the worst Jewish fears and prejudices–springing from history but not in present-day reality–about Christians and the evangelical movement in particular. It must be news to Mitt Romney to hear that after months of being told by the liberal media that evangelicals would never accept a Mormon as a leader, liberals are now making him the symbol of evangelical political ambitions.

Those who wonder perennially why Jews are Democrats need look no further than Dershowitz’s argument. The boundaries of ethnic voting are patrolled in this way among Jews (and blacks) by appealing to the worst fears of a somewhat insular group. Jewish Democrats did the same thing in 2008, when they tried to link Sarah Palin with Nazis (yes, Rep. Rob Wexler of Florida actually did that), as well as Christian conservatives.

Most of those Jewish voters for whom Israel is the number one issue have long ago decided that Obama has to go. Others, for whom Israel is only one among many issues, understand that Dershowitz’s economic argument is meaningless, and that Obama has presided over the worst recovery since the Second World War, made worse by his foolish spending and heavy-handed regulation. Those who still feel the tug of Dershowitz’s judicial arguments should ask themselves why it is that today’s “conservative” court has arrived at so many liberal decisions, and whether, in 2012, it really makes sense to fear a Christian pogrom in the United States.