Prime Minister Ehud Olmert has decided to commit the state of Israel to a much more intensive engagement with the Jewish communities of the Diaspora. Nothing that has leaked out of the first discussion on the issue, held at the Prime Minister's Office on Wednesday, and nothing in the record of this government or its predecessors, suggests that Israel understands the complexity and immensity of the challenge posed by the Israel-Diaspora relationship. Thus, while Olmert's initiative deserves praise, it also needs urgent direction. Let's review. Until the end of the 20th century, and for the two millennia preceding, the Jewish world was an archipelago of small and medium communities, with no single national community comprising more than perhaps 20 percent of the Jews at any given time. Technology limited contact so that, for example, dozens of relatively large communities within the Russian Empire did not have regular cultural interaction. Today, about 80-85% of the world's Jews live in just two communities, the US and Israel. Communication is instant and direct, offering unprecedented potential for greater coherence and understanding, but also making it impossible for any community to hide its dysfunctions. Thus, American Jewry's weaknesses are laid bare for Israelis to see, and vice versa. But - and this is key for well-meaning Israeli planners - as this awareness of weakness has grown, it has grown without context. It is, as with many other internet-age phenomena, "a mile wide and an inch deep." So while they hear more about each other than any other two Jewish communities in history, they are also among the most different Jewish communities in history. Like other Americans, America's Jews are passionately individualistic. Like other Americans, they have no patience or understanding for government intervention in their private lives, including the religious sphere, and they intuitively understand their Jewish identity as a choice that their society challenges them to make. In Israel, meanwhile few of us are asked to choose to be Jewish. Our identity is not a religious choice, but a natural, organic and innate sense of communal identification. This is the gap that a new Israel-Diaspora relationship must bridge - not one of communication, but of understanding. The new initiative will only succeed if it is the beginning of a generation-long project that engages American Jews in building a shared transnational Jewish culture. The initially suggested ideas - "rebranding" Israel, establishing Israeli cultural centers and unifying Israeli resources overseas that deal with Jewish identity - sound worryingly like a recap of old, arrogant attempts to impose Israeli cultural understandings on the American Jewish reality. What is required on both sides is a massive investment in education about each other at all levels (one of the weakest links in worldwide Jewish identity-building lies in the Israeli education system itself) and massive support for creating the artifacts of culture - literature, painting, sculpture, cinema. Both communities must engage in prolific translation of each other's literature, comedy, scientific research and the like, far beyond the fractional and half-hearted translation that takes place today dictated only by market forces. One of the most powerful weapons we've discovered for fighting the weakening bonds between Israel and US Jewry is the birthright program. The intercourse of cultures can create a shared culture, so it is imperative to develop a birthright program in the other direction as well. American Jewish culture is based on the English language. Teaching them Hebrew - as Israelis often suggest - will only happen in serious numbers after a shared culture already exists, when American Jews have some motivation to learn. Until then, our shared language can and will be bilingual. Perhaps with the smaller, scattered Jewish communities of the Diaspora - such as Italy and Belgium - the Israel-centric methods are correct. These communities do not have the resources to create their own cultural artifacts, to train their rabbis and carry on a separate literary community. But the American Jewish community, comprising 75% of the Diaspora, with three times as many professors of Jewish studies as Israel, is fundamentally different. The simplistic techniques which may work elsewhere won't work in America. The prime minister is right to turn up the heat on a discussion of this issue. If we do not develop this shared culture, the centrifugal forces at work in the Jewish world will drive us farther apart. Without both communities committed to building together, the Jewish people as a whole are immeasurably weakened in facing the challenges of the 21st century, which are turning out to be as profound and complex as those of the 20th.