"It's 1938", Benjamin Netanyahu is fond of intoning. The idea being that Iran is the new Germany, Ahmadinejad the new Hitler. But maybe events in the Middle East are more like 1958, when military officers overthrew the discredited Hashemite monarchy in Iraq; Egypt and Syria fused into a new pan-Arab entity, the United Arab Republic (UAR); Muslim nationalists threatened the fragile status quo of Lebanon; and nationalists demanded that the young King Hussein be toppled.
Yet pan-Arabism sewed the seeds of its own destruction: the UAR dissolved in 1961, Lebanese rebels were rebuffed by a US and French military show of strength; King Hussein not only survived but emerged stronger.
Of course, Israel cannot be blamed for worrying about the future. In the immediate term, it fears that the Muslim Brotherhood may take over Egypt and then jettison Cairo's peace treaty with Jerusalem.
But how likely is a Muslim Brotherhood victory? Secularists generally sparked off the current Egyptian uprising and the Brotherhood appeared to have been caught unawares. But it does enjoy support, winning half of all seats contested in the last election, until Mubarak effectively stopped the results and ensured his party's "victory".
Still, their roots run deep. Founded in 1928 by an Egyptian schoolteacher, they tapped into resentment against colonial rule. Primarily they remain conservative; their chief foes were Communism and now Western style globalism. No friends of Israel, their protégés are Hamas. Yet they have learned how to accommodate the powers-that-be, having backed the Free Officers coup of 1952, only to be outlawed in 1954. Encouraged by Sadat as a counterweight to leftists in the 1970s, they faced a Mubarak clampdown in the 1980s.
While founded in Egypt, the Brotherhood is represented in most Middle Eastern countries. But might they actually wield power in a regional domino effect? The answer varies from state to state. In Syria, they overplayed their hand and were crushed by Baathists in 1983. In Jordan, King Hussein effectively co-opted them and they still underpin the opposition. On Tuesday, while King Abdullah responded to demonstrations by sacking Prime Minister Rifai, the local Brotherhood swore fealty to the monarchy itself.
The notion that "Egypt is Iran" does not pass muster, notwithstanding fears that Islamists will again hijack a revolution begun by secularists. While Sayid Qutb, godfather of the anti-democratic jihadi stream, began as a Brotherhood ideologue, the mainstream Brothers have allied with Egyptian political parties. Having become a vehicle of dissent, it will be intriguing to see how they react in the new age of openness.
Might they seem like another atrophied old guard institution? Few have focused on their divisions between ageing seers and a younger breakaway group, Wasat (Centre).
Ordinary Egyptians- like Tunisians- seem fed up with being patronised. Perhaps the wittiest poster on display in Tahrir Square showed Mubarak alongside each of five US presidents: Reagan, Bush 1, Clinton, Bush 2 and Obama. But Egypt will have enough to worry about without risking US support by cancelling foreign treaties. As Roger Cohen wrote this week in the New York Times: "One big subject they are not talking about is Israel." For too long, corrupt regimes have pushed the "Palestine" button to divert popular rage. Only now, people are enjoying speaking out about their own problems for the first time.
Longer term, Egypt may wish to escape dependency on US aid. For now, though, the US-backed military is the one national institution that is respected and could work as a transition to the future.
Maybe this is not 1938 or 1958, but Egypt's own 1948, its moment of independence. If so, the words of Nachman of Bratzlav may offer succour to an understandably wary Israel: "The world is a narrow bridge; the point is, don't be scared." Nothing Israel does can change the will of the Egyptian people. Surely this is the first law of democracy, and as an established democracy, Israel should respect the 80 million Egyptians trying to find their own way across that narrow bridge.