When the police arrived at the scene of the crime on the morning of October 7, 1952, the body of the well-dressed passenger was slouched across the back seat of the Hudson car. His suit was stained by the blood still oozing from gunshot wounds to his neck and chest. The dead man was Chief Waruhiu wa Kungu, the senior African official under Kenya’s British administration.

The colonial government’s “tower of strength” was dead, the victim of a well-planned assassination in Nairobi, carried out on the orders of the leaders of the Mau Mau. Waruhiu’s murder led to the declaration of a state of emergency in Kenya that would last more than seven years. The war the British fought there — the first war on terror — has many parallels with more recent events in Iraq.

The local allies of the American coalition are crucial players in the effort to find a peaceful solution in Iraq, yet they are every bit as vulnerable to murderous assault as was Waruhiu. From lowly police officers and recently recruited members of the reformed Iraqi National Guard, to senior officials and politicians, all who have taken a public stand with the Americans are now targets for the insurgents. It was the same in Kenya, and there a poorly armed guerrilla force managed to assassinate more than 2,000 “collaborators”.

In Kenya the British consolidated local resistance to the Mau Mau by forming a militia, known as the Home Guard. These “loyalists” grew to number more than 60,000, but infiltration by rebel sympathisers was rife and caused a haemorrhage of intelligence.

Kenya did not have suicide bombers but attacks on police posts and prisons were made with the complicity of guards and warders, and the Home Guard and other locally recruited security agents provided a flow of arms and ammunition to the rebels.

In large part through British manipulation of local politics, the struggle in Kenya became a kind of civil war, with the Home Guard and African police thrown into the thick of it. In Kenya there were many atrocities and excesses on both sides, with attacks upon “loyalist villages” by the Mau Mau, and the systematic mistreatment of captives by the Home Guard.

Regular military forces also guided the counter-insurgency campaign in Kenya. In yet another echo of Iraq, as the British prepared to launch a vast assault upon the Mau Mau organisation in Nairobi it was the soldiers of the Black Watch who were brought in to quieten the countryside along the escape routes to the north.

The assault on Nairobi that began late in April 1954 was the largest cordon-and-search operation ever mounted. Operation Anvil sealed the city for five weeks. This was no Falluja. There was no “softening up” by bombing. Instead, a deliberate effort was made to capture and interrogate all suspects. It was in the poor African housing estates and slum warrens of Nairobi that the British Army began to hone the skills it would deploy in Basra 50 years later.

By the end of May 1954 more than 25,000 people had been detained in special camps, all suspected of Mau Mau sympathies.

Many returned home to find their property and belongings had been seized by “loyalist” opponents. Does fear of this kind of victimisation now plague Iraq’s Sunni minority, and prevent the Ba’ath party hardliners from negotiating? The British assault upon Nairobi was far less bloody than the American destruction of Falluja, and in the long run it would prove to be critical in undermining the supply lines and chain of command of the Mau Mau insurgents, but its immediate effect was to spark a new wave of violence.

The renegade groups involved became increasingly desperate and unpredictable. The aftermath of the Falluja assault seems to have provoked a similar pattern of continuing violence.

News stories about atrocities committed by the security forces in Kenya in 1954 were just as vivid as those in Iraq in 2004. Evidence came to light that the beating of prisoners was sanctioned by senior officials, and that the governor and his staff were aware of the character of the procedures being adopted, if not the details. Britain’s chief of police in Kenya, Arthur Young, became so enraged by official reluctance to prosecute senior officials that he resigned. British officials refused to acknowledge the wayward character of the system over which they presided. Instead, they were content to see hapless juniors prosecuted for individual acts of cruelty.

Then, as now, there were those who dismissed atrocity and torture as the necessary corollary of war. Special courts set up to hear the cases of insurgents nevertheless sent 1,090 men to the gallows — the majority of them hanged at a time when capital punishment had been temporarily suspended in Britain while parliament debated the abolition of hanging.

The nomination of Alberto Gonzales to serve as President George W Bush’s next attorney-general might be a signal that the law will continue to be manipulated in Iraq to facilitate the counter-insurgency campaign there. A report in Newsweek last week highlighted the role of Gonzales in the drafting of a “torture memo” that preceded the revelations at Abu Ghraib prison.

The hawks in the American administration have made it clear that they think the Geneva conventions, which came into force in 1949, are outmoded in the context of the “war on terror”.

In the British parliament of the 1950s Barbara Castle led Labour backbenchers clamouring to publicise the horrors in Kenya: the official death toll was 10,000, the real figure certainly double this. But when the final great scandal of the British colonial regime came to light in 1959, with the beating to death of 11 prison inmates at Hola camp, it was a Tory — Enoch Powell — who made the critical speech that condemned British actions. As we move into 2005, will we begin to hear similar voices from the right wing of American politics?

David Anderson’s Histories of the Hanged: Britain’s Dirty War in Kenya and the End of the Empire, will be published by Weidenfeld & Nicolson next week