They gathered in their tens of thousands in the streets and squares of the old city in the cold nights at the end of January. They were mostly young, educated and seemingly without leaders, which appeared to affect them not at all. They cheerfully defied the night curfews without fear and waved at the custodians of order, who mostly did not dare harm them. They had but one demand: the head of the administration must go. They carried his defaced pictures and hurled abuse at him, which, of course he did not hear, ensconced almost hermitically away from the crowds.

This would describe Cairo in 2011, but it would fit just as well to tumultuous happenings in Ahmedabad 36 years ago. The historic Navnirman agitation was in full swing in the principal city of Gujarat at the start of 1975. It then spread to Bihar and later still to other northern states. The Emergency followed in 1976. The Congress government at the centre lost the election in 1977, for the first time in the 30-year old independent India.

Then, as now, rising food prices were the trigger event. Gujarat was always sensitive to edible oil prices. Following two droughts in three years, the golden oil had climbed to the then unheard of levels of Rs 6 or more per kg. The mess bill of the LD College of Engineering hostels went up some 20%. Students were furious and after a short period of campus agitation, took to the streets. They were quickly joined by other students in the city.

The agitators suspected that the then CM, the late Chimanbhai Patel, had been bribed by the powerful oil barons of Saurashtra to allow them to jack-up oil prices. Mr Patel had become CM of Gujarat a scant six months earlier, after intriguing against his predecessor, the mild-mannered Ghanshyam Oza. Money power was widely presumed to have caused the change of guard.

The agitation spread to the rest of the state quickly, grinding its economy to a halt. And yet there were only a few leaders, mostly unknown beyond Ahmedabad campuses and localities. Manish Jani later joined the Congress and Ashok Bhatt became a Janata-BJP veteran of Khadia (he died last year after holding ministerial offices for over a decade). By March, Chimanbhai Patel had to quit. A motley coalition of the Organisation Congress, Congress rebels, Jan Sangh, Socialists, and independents took office, under the leadership of Babubhai J Patel, a benign, sagacious Gandhian leader not unlike Mohamed ElBaradei, coming out of retirement. The group called itself the Janata Morcha, the beginning of the Janata experiment in India. Jaya-prakash Narayan was still in his ashram in Patna at this time and not involved.

What followed in 1976 and thereafter is well-known and does not need to be repeated. The common thread between the agitations in Gujarat in 1975 and those in Tunisia and Egypt in 2011 is that they were all nearly spontaneous, sparked off by obscure and small beginnings and grew ever so large rapidly as to take down ancien regimes almost as if they were swept away by a tidal wave.

Students of Chinese history are aware of the concept of Heaven?s Mandate. It is believed that various dynasties ruled so long as they enjoyed this mandate and were overthrown when they lost it. Obviously, the mandate signified a virtuous governing formation. It was withdrawn when the rulers became unmindful of their duties to the people.

The modern equivalent is the consent of the ruled. Even the most oppressive dictator cannot survive indefinitely without the assent of the people. Popular anger?no matter what caused it? targetted at Ben Ali and Mubarak, like that at Chimanbhai Patel more than a generation ago, signified a withdrawal of the consent of the ruled.

The general disaffection of masses arises from a widely shared perception that those in power have stopped listening to them and are content to pursue solely their own interests. Even small incidents are enough to convince people that their understanding is valid. Internet, mobile phones and social networks may have helped spread the word instantly in Tunisia and Egypt, but in Gujarat of 1975 and North India of 1977, even print media did not reach most people or were muzzled (electronic media were still two decades away). Just the word of mouth sufficed and spread quickly. Every story of greed of the leaders or excesses of the Emergency found ready acceptance without any documented proof or oratorical brilliance.

Another thing follows. The people lose their fear of the police. All rulers exercise their coercive power through a small uniformed force, which strikes dread in the hearts of people. When the ruled withdraw their consent, they see the police as enforcers of a discredited usurper, not legitimate authority. The army is still seen as neutral. Soon, protesters make friendly gestures to its members, who often reciprocate. In worst case scenarios, unarmed masses simply overrun the troops leaving many martyrs, who inspire them to further action, as colonial powers have found out throughout history.

The North African ruling elite was complacent in its belief that its people were becoming better-off and had no real choice, as it had shut off all means of dissent and its expression. Indira Gandhi, too, believed that she knew what was best for Indians and choked communication. The regimes stopped receiving the bad news that the ruled were restless after a generation or more and were withdrawing their consent. No system of governance or leader is powerful or charismatic enough to withstand this cataclysm.

The author has taught at IIMA and helped set up IRMA