Yasmin Alibhai-Brown: The cloud that hangs over the Arab Spring

This year, Eid, the festival at the end of Ramadan, was celebrated with incomparable ecstasy across many parts of the Middle East. After an arduous month of fasting, the day is always packed with pleasures but this time, political release and hope was in the joyous mix. I've been in the region researching my next book. From the balcony of my hotel in downtown Cairo, you can see the now-famous Tahrir Square, where the people's revolt against the dictatorial President, Hosni Mubarak, started and ended this year.

But the precinct, symbol of the uprising, was unnaturally quiet and nervy, surrounded by soldiers. The Israeli Embassy area also felt markedly edgy. So, it isn't a surprise, really, that on Friday masses came out to demonstrate again and some then tried to destroy the embassy. But it is profoundly depressing – and may stall recent Arab political developments. On my own exultant, instructive journey, I found Israel was sometimes the cul-de-sac, always the excuse, often the boulder, everywhere venom in the bloodstream causing severe paralysis and rashness of mind.

There is no question that grave historical injustices were committed by Britain and the Europeans against the Palestinians. Their land was stolen to create a Jewish state in order to assuage the guilt of the Holocaust. Millions of their dispossessed are forced endlessly to roam the earth or remain in refugee camps from cradle to grave. Those who can't leave lose more rights, more land, all dignity and aspiration. If you can find it, read the beautiful, poignant book The Palestinians, by Jonathan Dimbleby and photographer Don McCullin. You will then understand why the Palestinians and their many supporters carry on fighting for justice.

But that injustice did not make Arab dictators, nor can it explain why most Arab nations are in a state of political, social and economic collapse. Their citizens were at long last facing up to these endemic problems when they turned on Israel almost as a welcome distraction.

Rage against Israel's policies is completely justifiable, but not when expressed in this way and at this crucial time of incredible transformation.

The possibility of democracy has freed spirits in every way. In Egypt women now wear headscarves covered in balls, and flowers, feathers and sequins, more colourful than the hats at Ascot. Muslims walk hand in hand or cuddle on streets; it wouldn't happen in Bradford or Southall. In cafés you hear philosophical and intellectual debates you would not get in our Starbucks. Writers and movie-makers tell me they felt they have emerged from airless, lightless dungeons and feel their creative lines opening up.

Global populations have been inspired by Arab youngsters for the first time in centuries. It's incredible, really – but Israeli-bashing now will kill all that and reassure those who believe Arabs are no good at anything but blaming others.