If there is one lesson to come out of this week’s controversy over Jerusalem and the US Democratic Party platform, it’s this: both parties believe the Jewish vote could be an extremely important factor in this year’s presidential election. And they’re right.Jews may constitute only two percent of the national population, but the Jewish communities in swing states such as Florida, Pennsylvania and Ohio could have a major impact. In Florida (29 electoral votes), they make up 6% to 8% of those who cast ballots. Jews are 4% of the voters in Pennsylvania (20 electoral votes), where John Kerry beat George W. Bush by just 51%-49%. Jewish voters are between 2% and 3% of the electorate in Ohio (18 electoral votes), where Jimmy Carter (in 1976) won by less than 1% and Bill Clinton (1992) won by less than 2%.The writer is director of The David S. Wyman Institute for Holocaust Studies, and co-author, with Prof. Sonja Schoepf Wentling, of the new book Herbert Hoover and the Jews: The Origins of the ‘Jewish Vote’ and Bipartisan Support for Israel.Not surprisingly, then, references to Jerusalem have been a staple of both party platforms for many years.The Democrats, in fact, were first. Their 1972 platform declared that the United States should “recognize and support the established status of Jerusalem as the capital of Israel” and that “the US Embassy should be moved from Tel Aviv to Jerusalem.”In 1980, the Republicans got on board, but only partly so. Their platform asserted: “Jerusalem should remain an undivided city with continued free and unimpeded access to all holy places by people of all faiths.” That wasn’t the same as saying the US should recognize Jerusalem as Israel’s capital, but it did in effect reject the Arab position that Jerusalem should be redivided as it had been from 1948 to 1967.Meanwhile, though, there were rumblings of dissent within the Democratic Party. In 1980, President Jimmy Carter said openly that he disagreed with the party’s position on Jerusalem. And in 1988, Arab-American activists and supporters of the Rev. Jesse Jackson managed to get the reference to Jerusalem omitted altogether.Four years later, with Bill Clinton as the nominee and the Jackson wing effectively marginalized, the Democratic platform reaffirmed that Jerusalem “is the capital of the state of Israel,” although it did not repeat earlier pledges about moving the US embassy from Tel Aviv.The turning point in the history of Jerusalem as an American political football came in 1995, when Congress overwhelmingly approved the Jerusalem Embassy Relocation Act. Initiated by Republican Senator Bob Dole, the legislation acknowledged Jerusalem as Israel’s capital and required relocation of the embassy.President Clinton insisted on including a provision that permits postponing relocation of the embassy if the president believes a delay is necessary for "national security." Both he and his successors repeatedly invoked that waiver, which is why the U.S. embassy is still in Tel Aviv.BUT THE principle of bipartisan congressional support for Jerusalem as Israel’s capital thus established, both parties’ platforms soon followed. Every Democratic and Republican platform since 1996 has recognized Jerusalem as Israel’s capital, and several of the GOP platforms have specifically called for moving the US embassy from Tel Aviv to Jerusalem.So what happened at this year's Democratic convention? Somebody – nobody has yet owned up to it – decided to drop the longstanding language on Jerusalem. That decision was, arguably, consistent with the Obama administration’s policies on the issue. The administration has pressed Israel to refrain from building apartments in some parts of Jerusalem. References to Jerusalem as Israel’s capital have been removed from the White House web site. And US officials have declined to acknowledge Jerusalem as Israel’s capital when asked by reporters. Clearly the administration’s position is that Jerusalem is negotiable.But politically wiser heads at the convention obviously prevailed. They recognized that abandoning Jerusalem could provoke Jewish voters in Miami or Cleveland to abandon the president. In a hastily-arranged voice vote on Wednesday afternoon, the platform’s previous language on Jerusalem was restored.Platforms are symbolic. Candidates are not bound by them. But symbols are important. And when both parties embrace the same symbol, a bipartisan consensus is established.Sixty-eight years ago, a bipartisan consensus was established on the question of creating a Jewish state. In 1944, Benzion Netanyahu (the father of Israel’s current prime minister) helped convince former president Herbert Hoover and other senior Republican figures to adopt the first-ever plank calling for rescue of Jews from Hitler and creation of a Jewish state. That forced the Democrats to quickly follow with an almost-identical plank in their own platform. With both parties in agreement, the path was clear for America-Israel friendship to become a permanent part of American political culture.Likewise, the 1995 Jerusalem embassy legislation and the 1996 Republican and Democratic platforms appeared to establish a similar bipartisan consensus on Jerusalem. By restoring their party’s traditional language on Jerusalem, the Democrats have upheld that consensus. At least for now.