The despots who have ruled the Arab world for half a century are not giving up without a fight.

In Syria and Yemen, state-sponsored violence has proved counter-effective. Protesters were enraged rather than intimidated.

A remarkable aspect of the Arab uprisings is that ruler after ruler is making the same mistakes that brought down Zine al-Abidine Ben Ali in Tunisia and Hosni Mubarak in Egypt.

Local tyrants, from Muammar Gaddafi in Libya to Ali Abdullah Saleh in Yemen, behave as if they had joined a collective political suicide pact whereby they alternate mindless violence and inadequate concessions in just the right quantities to discredit themselves and undermine their regimes.

Recipes for staying in power that have served them so well since the early 1970s suddenly don't work any more. This affects almost all the Arab states, monarchies as well as republics, since they have functioned in almost the same way.

The typical Arab state was based, with some local variations, on a single model: a kleptomaniac elite, often originating in the army and united by sect, tribe or extended family, monopolises power at the top.

The government is a corrupt and bloated patronage machine used to reward cronies and followers. The most animate part of the state is the Mukhabarat, as the security services are generally known, which crushes all forms of dissent. This type of autocracy was buttressed in the Middle East and North Africa by huge oil revenues. Those without oil themselves could get aid from those who had it. Oil states are, by their nature, undemocratic.

The Arab autocracies could also look to superpower backing which, up to 1990, meant the United States and the Soviet Union. After the fall of communism the US was the sole contender for hegemony, though this was never quite complete because Washington failed to resolve the Israeli-Palestinian struggle or overthrow the government in Tehran.

For the states most dependent on the US, such as Egypt and Jordan, US political domination meant control of crucial security institutions.

US predominance in the region started to be undermined when President George W. Bush overplayed his hand by invading and then failing to hold Iraq. The neo-cons spoke of regime change in Damascus and Tehran, while the US gave support to Israel.

The US's Arab allies discredited themselves in the eyes of their own people by conniving in or secretly supporting Israel's bombardment of Lebanon in 2006 and Gaza in 2008 and 2009.

It is easy in retrospect to dwell on the fragility of the Arab states if they ever came under sustained pressure. But until a few months ago they appeared to be the only model, not just for rulers but for those who wanted to replace them. Yasser Arafat and Fatah, having fought for so long for a Palestinian homeland, in the 1990s established in the West Bank and Gaza a parody of the corrupt Arab police state.

The Iraqi Shia religious parties, elected to form a government in 2005, soon began to set up a Shia-dominated version of Saddam Hussein's regime. By one count, there are now eight or nine competing intelligence services and prisoners are routinely tortured.

So is the old model of the Arab security state as moribund as it ought to be? In Tunisia and Egypt, the army and the ruling class assented to Ben Ali and Mubarak being deposed to prevent an uprising turning into a revolution.

Many things have changed in the Middle East and North Africa, but not everything. The influence of Facebook and Twitter are exaggerated but satellite television - and, above all, al-Jazeera - the mobile phone and the internet have been crucial in reducing government control of information and communications.

Arab rulers can still press some buttons that work. Western pundits have been querying whether the fall of Saleh in Yemen would open the door to al-Qaeda in the Arabian Peninsula. The presence of this group of about 300 members in a country of 24 million has been skilfully exploited by the regime to extract aid and weapons from the US. In Bahrain, the monarchy, having brutally suppressed protesters, is pretending that unrest among the Shia majority was anti-Sunni and orchestrated by Iran. King Abdullah of Saudi Arabia is trying to quell unrest by repressing it and buying off protesters with billions of dollars.

Such ploys may succeed for a time but the day of the classic Arab security state is surely over.