For many Israelis, he is that man with a beard whose achievements are - as one Tel Aviv pundit claimed - "irrelevant" to modern Israel. For American Jews, he is an unknown or just a name pulled out of history, often unconnected to any real sense of his importance. But as Jews celebrated Israel's 58th birthday last week, it's appropriate to recognize that without Theodor Herzl none of the major Jewish achievements of the past 100 years would have been possible. Okay, you might answer, Herzl is the founder of the modern Zionist movement. Place a wreath on his grave and wave the blue-and-white flag if you like, but what exactly does he have to do with modern Jewish dilemmas? But with all due respect to those on the self-proclaimed cutting edge of modern Jewish culture in both Israel and the United States, the truth is that thinking seriously about the guy with the beard is a lot more relevant than the self-important musings of many of our contemporary intellectuals. That's not just because without Herzl - and what he did in his short career before his tragic death at age 44 - there is no State of Israel and all that it means to the Jewish people. It's because Herzl the man is a profoundly compelling figure whose life bears special importance not just for Israelis, but also for those of us in the Diaspora. To say that flies in the face of the tide of Jewish opinion in America, where surveys have been telling us for years that Jews are less and less interested in Israel and its complicated politics and security dilemmas. After all, contemporary American Jewish life, with its unlimited freedom and the ability of Jews to ascend to the top of virtually any field of endeavor, seems to be a standing rebuke to classical Zionist theory, which claimed that Jews could only truly prosper in their own independent country. BUT THE closer we look at Herzl, the more we see someone who is, in fact, the perfect role model for a muddled Diaspora struggling for a sense of its own identity. Herzl was, after all, as assimilated as most American Jews are today, with a strong sense of pride in his identity but little sense of what it meant and little interest in living a Jewish life. Like many in the contemporary Diaspora, he was more at home in the secular culture of his day than its Jewish counterpart. But after witnessing the degradation of Alfred Dreyfus, a French Jewish officer falsely accused of treason - a harbinger of the tragedies that were to follow in 20th-century Europe - Herzl decided to act. His pamphlet called The Jewish State launched political Zionism. And as he himself predicted, a little more than 50 years after his movement's founding at the first Zionist Congress in Basel, Switzerland, Jewish statehood was a reality. As Dan Polisar, the man recently appointed by Prime Minister Ehud Olmert to head a national council for promoting the legacy of Herzl, points out, it is "Herzl the visionary" who has a great deal to say to us today. And that is the key phrase. Herzl was a dreamer, not just of a haven for oppressed Jews (though that was a paramount concern to him), but a place where Jews could realize their full potential. Polisar, the American-born president of the Shalem Center in Jerusalem, explains that "Herzl's Zionism was, in part, a reaction to anti-Semitism on a level that American Jews would not be familiar with today. But it also had a strong positive side. He believed that it was necessary for Jews to develop their own culture and ideas in order to make a unique contribution to the world." Despite the post-Zionism of some of Israel's intellectual and cultural elites, Polisar insists that most Israelis instinctively turn to Herzl as a unifying figure because, unlike almost every other founding father of the country, he is someone who is above politics and not linked to purely military achievements. Herzl is someone, as Polisar puts it, "whose principal accomplishments were those that were intangible and in the realm of the world of ideas. There's still great respect for military leaders, but even more respect today for visionaries." AND OURS is a time when such visionaries are needed more than ever. Given Israel's intractable security challenges and with assimilation in the US rising as fast as anti-Semitism overseas, at times it seems as if all solutions are impossible. Who better for us to emulate than a person who came up with a dream - the return of the Jews onto the stage of history - that virtually everyone thought was impossible at the time? If his struggle has been forgotten and his brilliant ideas obscured by the passage of time, reviving his legacy has become a priority that, fortunately, some in Israel are trying to accomplish. Two years ago on the 100th anniversary of his yahrzeit, the Knesset passed a law enacting an annual Herzl day on the day of his birth, the 12th of Iyar in the Hebrew calendar, which falls this year on May 10. On that date, among other commemorations, ceremonies will be held at the redesigned museum dedicated to him, built on the edge of the capital's Mount Herzl Military Cemetery where he and other Israeli heroes are buried. Israeli television will also air documentaries about his legacy. But the day will pass almost without comment abroad. Polisar, whose council is supervising the festivities, hopes that in future years, Jews abroad will latch onto the holiday. Let's hope he's right. Because in the story of Herzl, of his coming to embrace a proud Jewish identity and having the courage to contradict every bit of the conventional wisdom of his own day, is a hero who ought to resonate in the heart of all who believe that the Jewish people and their heritage must not perish. The 12th of Iyar should always be a day to celebrate Jewish dreams and dreamers, with the centerpiece being the honoring of the greatest of our visionaries. As Herzl famously wrote in the preface to Alteneuland, the futurist novel composed to fully articulate his dream of Israel: "If you will, it is no fairy tale." At a time when Jewish survival, both physical and spiritual sometimes seems as doubtful as ever, his is a life we need to embrace more closely than ever before. Happy Herzl Day! The writer is executive editor of the Jewish Exponent in Philadelphia.