This week Jews all over the world celebrated the 70th anniversary of the founding of a sovereign Jewish state in the Land of Israel. Seventy years is a lifetime, and today the number of Jews left in the world who remember a time without Israel is dwindling.Seventy years is a time for reflection. It’s a time to take stock of the past and look to the future.On the one hand, the founding fathers are now gone. Those who fought for independence are now an endangered species.It is now their grandchildren who are in charge. They must wonder how much can they possibly appreciate the need for Israel. How can they, who have no memories of a time when Jews were defenseless, possibly fully understand the responsibility that now rests on their shoulders? How can they sustain the Zionist ethos, especially when the vast majority of Jews here are no longer educated about Judaism, as their grandparents were? How long can Zionism sustain itself, divorced from the very Judaism from which it sprung? How much longer can holidays like Shavuot and Sukkot be celebrated in the vacuum of the experience of God or covenant? The attempts by the kibbutzim of yesteryear to turn those holidays into agricultural ones have no meaning in the Start-Up Nation.Already in the 1940s Berl Katznelson said, “We came to the Land of Israel to build a generation of heretics but succeeded only in building a generation of ignoramuses.”I have been here for 25 years now, and I am shocked by the amount of Jewish illiteracy that plagues the Israeli public. I remember when I first arrived here I spent a Shabbat in Tel Aviv. On my way back from synagogue that morning, I passed by a café that was open, and old men were sitting around the table bareheaded, drinking their morning coffee with humashim opened, learning the weekly Torah portion. It amazed me then, and I miss it now.A couple of years ago, I was at a hotel on Shabbat. On the next table was a large, extended family.The religious-looking grandparents sat at the head of the table singing Shabbat songs, while their children wearing folded kippot sang along, while the grandchildren sat at the end of the table bareheaded and texting under the table.The thought that occurred to me then was: what will happen when these grandchildren become the grandparents? What Jewish values will they give to their grandchildren? Will they sit at the heads of their tables singing Shabbat hymns? Patriotism in the 21st century is withering, along with the idea of a nationstate.Israelis cannot be just patriotic. This will not be enough to sustain Israel.Israel must be rooted in its long past as part of the Jewish people and its story.Zionism must be taught as the physical and material manifestation of the hopes and dreams of our people.While, from a human point of view, Israel is now “old,” from a state point of view it is just a baby. When the United States celebrated its 70th anniversary in 1846, its size, excluding the territories, was only half of what it is now, slavery was legal, and women couldn’t vote. The US had yet to become the country we all know and love. It had not yet ripened to internalize the very same democratic principles upon which it was founded. Jefferson’s words proclaiming all men to be equal was a promise that had yet to be fulfilled.Israel at 70 is much the same. On the one hand, it has exceeded the wildest dreams of the founding generation.More Jews than ever before in Jewish history live in safety and security, either in Israel or in the long shadow it casts around the world. More Jews study Torah, observe Shabbat, keep kosher than ever before in Jewish history.Judaism and the Jewish people are thriving.On the other hand, Israel has failed to deliver on many of the hopes we had for it.Israel has many challenges ahead of it. Besides the obvious military threats, Israel will have to reckon with who it wants to be. Now that Israel is growing older, what kind of role does it want to play for Jews and the world at large? How will Israel balance its promise to be both a Jewish state and a democracy? When these two values come into conflict, which will yield? How does Israel express its Jewishness in a way that is noncoercive religiously but fully embracive of its deep spiritual well? Judaism is a religion of mitzvot. The very word “mitzva” means commandment. How do we teach the commandments to a public that does not recognize the Commander or His authority over us? If we don’t answer these questions precisely right, Israel will not be here in the future.As we celebrate Israel’s 70th birthday, we should bear in mind that since the time of King David, no Jewish state has lasted more than 80 years. That should give us pause.The writer holds a doctorate in Jewish philosophy and teaches in post-high-school yeshivot and midrashot in Jerusalem.