The demonstrations began again in Iran last week, only two years after the ‘Woman! Life! Freedom!’ movement convulsed the country for months. However, the current protests are potentially much broader than that episode because they are driven by the collapse in Iran’s currency, the rial (now 1,420,000 to the US dollar) and the explosive rise in the cost of living.

The last round of demonstrations, arrests and a few executions really engaged only the more secular and better educated part of the population – half, at most. The other half may not all love the regime, but they didn’t really care much about the fate of Mahsa Amina, the Kurdish girl who was beaten to death in prison for letting too much hair show under her hijab.

Whereas the cost-of-living crisis affects everybody. Moreover, since the same crew of Islamic divines has had the final say in Iran for the past 46 years – indeed, the very same man, Ayatollah Ali Khamenei, has been in charge since 1989 – there is no doubt about who is responsible for the current difficulties.

This creates the opportunity for a much wider coalition of forces in favour of radical change.

Maybe the demos will just peter out again in a few weeks or months as many other protests have done, but much has changed in Iran’s external environment since the last protest.

Of the Iranian regime’s proxies as recently as two years ago, all but one are defunct or gravely weakened. Syria has changed sides, Hamas in the Gaza Strip is defeated and may be forced to disarm, Hezbollah in Lebanon faces the same fate, and only the Houthi in Yemen are still useful allies.

It’s therefore time to consider what a post-Ayatolllah Iran would look like. In an era of sudden big changes after decades of near-stasis, almost anything is possible – but some possibilities are bigger than others. For Iran, most of the prospects are bad.

There could be a non-violent revolution that works like the Shah’s overthrow in 1979. Non-violent protesters came out in ever greater numbers, offering themselves up to be slain by the ‘security’ forces. In the end, the enforcers themselves grew sickened by the scale of the slaughter and refused to shoot the citizens anymore.

It was a style of protest by self-sacrifice that is deeply embedded in Shia Muslim tradition, but this generation’s rebels do not have the religious fervour that drove their grandparents almost half a century ago. Moreover, shaming the regime’s henchmen into abandoning their masters is not a credible strategy.

Non-violence has had a poor success rate in recent uprisings, and in terms of religion the shoe is now on the other foot in Iran. The men of the Islamic Revolutionary Guard Corps (IRGC) and the Basij militia who protect the regime believe God is on their side, and the Supreme Leader would not just walk away when the death toll got too high like the Shah did in 1979.

Could the protesters who are now chanting ‘Death to the Dictator’ bring down the regime by force? They probably have the support of most urban Iranians, and the big cities are where the outcome will be decided – but the only way they can get large quantities of weapons is if significant numbers of the IRGC and the Basij defect to them.

That, alas, is the ‘Syrian’ model. Young, non-violent Syrian protesters demanded an end to the tyrannical Assad regime in early 2011, and were shot down in such numbers that their leaders were replaced by more violent people. Ethnic and religious minorities seized the chance to break away, and the confrontation grew into a civil war that lasted an entire decade.

About half a million Syrians were killed. Almost half the entire population was displaced internally or abroad, and most of the country is still in ruins. Ahmed al-Sharaa, a former jihadi leader, overthrew the long-ruling dictator Bashar al-Assad in a lightning offensive one year ago, but the true character of the new regime remains to be determined.

Multiply that by four (Iran has 80 million people), and you have a vision of what Iran might look like if an originally non-violent pro-democracy movement is driven to take up arms against a ruthless regime: the entire country devastated, with tens of millions of people displaced.

Oh, and don’t forget that Iran is a former empire, and its population is therefore very diverse: Persians, Turks, Kurds, Arabs, Baluchis and Lors. If you ever broke that omelette up, you’d never put it together again.

It’s easy to say that the old regime must go (and it must). But it’s hard to believe that what comes next will be much better.

Gwynne Dyer’s latest book is Intervention Earth: Life-Saving Ideas from the World’s Climate Engineers