In late August, after extended verbal clashes between Israel and Egypt, which followed a deadly terror attack on Israel emanating from Sinai and Israel's aggressive response to it, a Saudi newspaper already foresaw "the ghost of a new crisis ... on the horizons of the two countries." No, the paper wasn't anticipating an Egyptian mob's shocking September 9 siege of Israel's Cairo embassy. Rather, it was the effects of a ban issued by the Egyptian agriculture minister on the export of lulavs, a key ingredient in the observance of the festival of Sukkot.

Egyptian palm-frond production is big business. Israel imports somewhere between 600,000 and 700,000 lulavs annually and has come to depend on Egypt's crop for Sukkot. This year's harvest holiday, which begins next Wednesday evening, comes as Israel is still coming to terms with the Egypt emerging in a post-Mubarak era.

It's not the first time that lulav sales have been a bone of contention. Egypt stopped exports to Israel in 2005, claiming that harvest of palm fronds hurt date output. A year later, though only a short time after the Second Lebanon War, Cairo and Jerusalem were able to find a quiet solution to the lulav issue, according to a confidential missive from the U.S. Embassy in Cairo in 2006, revealed by Wikileaks. "[D]espite the suspension of the [Egypt-Israel agricultural] working group's activities," Ambassador Frank Ricciardone reported to Washington, "Egypt would permit export of 500,000 palm fronds to Israel in time for the Jewish holiday of Sukkot."

American officials continue to show an interest in this vexing issue. Last week, U.S. Representative Howard Berman of California wrote to Egypt's U.S. ambassador, imploring him "to take all necessary steps to prevent any disruption in the supply of lulavs" to Israel, many of which are re-exported to America. Berman suggested that "the ban ... was imposed for purely political reasons," and that's likely the case. But is it possible the congressman was not seeing the palm grove for the trees?

If Egypt uses this important Jewish religious symbol to express its displeasure with Israel, it's also true that so long as Mubarak was in charge, Israel enjoyed Egyptian complicity in its blockade of Gaza and its overall strategy vis-a-vis the Palestinians.

Now that Mubarak is gone, Israel can expect relations with its Arab neighbor to bump along from crisis to crisis. Already, in addition to the border attack near Eilat, and Israel's response, which left five Egyptians dead, and the embassy invasion, we have seen repeated attacks on the pipeline carrying Egyptian natural gas across Sinai to Israel.

Mubarak was willing to cooperate with Israel, but he was encouraged to do so by Washington, which provided gargantuan military and aid packages to both parties. Now, the situation is different, and the United States is concerned. This week, Leon Panetta made his first trip as defense secretary to Egypt and, in his words, to an "increasingly isolated" Israel. His mission: "to ask them how we can be helpful in trying to improve those relations." Yet Panetta did not even succeed in securing the release of Ilan Grapel, an American-born Israeli student imprisoned in Cairo on charges of being a Mossad agent. Under Mubarak, such an incident would have been handled behind the scenes.

We can take comfort in the fact that a full 71 percent of Egyptians want to uphold "the legal state of peace" with Israel. But rest assured that, whatever party triumphs in the long-awaited Egyptian elections (legislative elections are set for late next month ), day-to-day functioning of that pact will look different afterward. In the meantime, the ruling military junta is discovering its leverage over Jerusalem. With more than half of Egyptians favoring an end of natural gas sales to Israel, expect the renegotiation of energy agreements - at the very least.

Clearly, Egypt's Supreme Council of the Armed Forces is not yet confident in its rule. The storming of the Israeli Embassy, for instance, might be seen as the military allowing demonstrators to let off steam, while diverting attention from the fact that the junta is unelected and is itself a target of protest.

The sooner Israel's government internalizes the fact that it can no longer manage the "Egypt file" on a strictly bilateral basis, the better. A post-Tahrir Square regime will inevitably be more responsive to public opinion and, as such, committed to pushing those issues most likely to ruffle Israeli diplomatic feathers, chief among them Palestinian independence. (It should be remembered that the Camp David Accords included in their framework a call to resolve "the Palestinian problem in all of its aspects." )

In this sense, and considering the season, perhaps Israel would do well to think of its treaty with Egypt in terms of an etrog, that other essential Sukkot accessory. Any damage to the pitom - the stem - makes the costly fruit un-kosher. If the Camp David Accords are not cushioned by smart strategy and are instead taken for granted - which would be akin to the pitom getting knocked off - I fear that Israel won't be able to make sweet jam out of that spoiled citron.