The Russian army's decision to replace the famed Kalashnikov as its standard infantry assault weapon is so shocking that its 92-year-old inventor, Lieutenant General Mikhail Kalashnikov, cannot be told. The defence ministry fears the news might kill him. If it did, he would be only the latest casualty of a rifle that has killed millions since it went into production in 1947.

As a young tank sergeant recovering from wounds suffered fighting the Nazis in 1941, he conceived a weapon to match the German Sturmgewehr 44. It did not go into production until after the Second World War, when it became the Red Army's standard field rifle and the favourite of liberation movements, terrorists and gangsters.

Estimates of the number of Kalashnikov rifles in circulation run as high as 100 million, making it what the Russian president, Dimitri Medvedev, called "a national brand which evokes pride in each citizen".

"It is the Germans who are responsible for the fact that I became a fabricator of arms," Mikhail Kalashnikov later said. "If not for them, I would have constructed agricultural machines."

War turned the son of kulaks, slightly richer peasants who Stalin banished to Siberia, from ploughshares to swords. His sword was the Avtomat Kalishnikova 1947, popularly known as the AK-47, for the year it went into production.

Warsaw Pact armies adopted it, followed by nearly every anti-colonial independence insurgency of the post-war world. Larry Kahaner, author of AK-47: The Weapon That Changed the Face of War, wrote in TheWashington Post: "The AK blew away old battlefield calculations of military superiority, of tactics and strategy, of who could be a soldier, of whose technology would triumph."

Mikhail Kalashnikov's assault rifle equalised the battle between modern western armies and third world liberation movements. It was to independence fighters what the Winchester repeater, the "gun that won the West", was to American frontiersmen. Only later did the Kalashnikov fall into the hands of drug traffickers, slave traders and terrorists. Modern criminals adopted it the way Prohibition-era gangsters had the famed Thompson or "Tommy gun", previously the weapon of the FBI and other G-men who were pursuing them.

The AK-47's strength was its simplicity.

"It is very important because a soldier doesn't have university degrees," Lt Gen Kalashnikov said. "He needs a simple and reliable weapon ... There's simply no time to figure how to operate a complicated weapon and press many buttons when the enemy is advancing on you."

In Vietnam, the American soldier's M-16 may have been more sophisticated and powerful, but the AK-47 worked without jamming through mud and monsoon. Peasants from Southeast Asia to South America made it their weapon of choice, and its distinctive form ended up on flags from Mozambique's to Hizbollah's. The "Kalashin", as it is called in Arabic, also defined an era in the Middle East. Arab armies deployed it, as did Yemeni tribesmen, Kurdish guerrillas, Lebanese militias and the Palestine Liberation Organisation. A Palestinian friend of mine said of the Israeli siege of West Beirut in the summer of 1982: "All the real fighting is done with Kalashnikovs. The rest is just sound effects."

When the Israelis attempted to force their way into West Beirut, Palestinian and Lebanese fighters fired their Kalashnikovs from the rubble to hold them back. The Israelis were not able to enter until after the PLO departed and took its Kalashnikovs with it.

I cannot recall covering a war since my first, the Arab-Israeli War of October 1973, in which the Kalashnikov was not a salient feature. Zimbabwe African People's Union and Zimbabwe African National Union fighters carried them in Rhodesia, and the Eritreans fought with them against Ethiopia for more than 30 years. Hizbollah used far more AKs than suicide bombers against the Israeli army in south Lebanon, eventually driving it back into Israel. In Lebanon's civil war, nearly everyone used them. Only the Lebanese army, which for the most part remained neutral for 15 years of fighting, carried French and later American rifles. I asked a Lebanese general why the Ministry of Defence had placed a large order for M-16s, when the AK-47 was probably the superior weapon. His answer was along these lines: "When you carry a Kalashnikov, you are a guerrilla. When you have the M-16, you are a soldier." It was part of the indoctrination of the soldiers that they were not militiamen, but regular army troops defending the state rather than a sect or a party. The M-16 was as important in that self-image as the uniform.

As with one person's terrorist being another's freedom fighter, a weapon symbolises freedom to one side and terror to another. To Vietnamese, Palestinians, Angolans and Guatemalans, the AK-47 was a tool for achieving justice. To the Hungarians in 1956 and the Czechs in 1968, when Soviet troops used it to crush their revolutions, it was an instrument of repression. In Afghanistan, it played a more ambiguous role. The Soviet army used it against Afghan villagers. The CIA, knowing American rifles were neither popular nor easy for guerrillas to use, provided the mujaheddin with the Russian-designed weapon to kill Russians. It was one of many wars in which both sides used the same arms and ammunition.

Before the Kalashnikov found its way into most of the third world's arsenals, some independence fighters favoured the Tommy gun. The Irish used it against the British and in the civil war that followed Britain's departure and the division of the country. It featured in a number of rebel songs such as The Jolly Ploughboy:

We're all off to Dublin, in the green, in the green,
Where the helmets glisten in the sun,
Where the rifles flash and the bayonets clash
To the music of a Thompson gun.

By the 1970s, when the killing in the North began in earnest, the IRA had switched to both the Kalashnikov and the American Armalite AR-18. The Kalashnikov, easier to obtain and cheaper, was more evident. The Soviets spread it worldwide by licensing other communist countries such as China, Czechoslovakia and North Korea to produce and export it.

"The AK-47 has become the world's most prolific and effective combat weapon," Larry Kahaner wrote, "a device so cheap and simple that it can be bought in many countries for less than the cost of a chicken."

Kahaner estimates that the weapon kills about a quarter of a million people annually. Its victims are buried in the ghetto of south central Los Angeles, the forests of eastern Congo and the mountains of Colombia.

Mikhail Kalashnikov stayed in the arms business all his life, improving on his original design and attending arms fairs around the world to sell it. The terms of his agreement with the Red Army left him with no royalties from the sale of millions of weapons, but since the demise of the Soviet Union he has received money from merchandising T-shirts, ashtrays and other AK-themed memorabilia. President Medvedev made him a Hero of Russia, and a bronze statue of him stands in his hometown to remind Russians of the country's most famous export after vodka. As the Russian army prepares to abandon Kalashnikov's famous rifle, the Russian soldier does not know what he will carry in its place.

"We are designing new firearms, and we currently have 10 million Kalashnikovs for our army of one million servicemen," General Nikolai Makarov, the Russian Armed Forces chief of general staff, told Reuters. "So the reserves we have will be more or less enough."

The Red Army was Kalashnikov's first customer, but it will not be his last. Factories around the world guarantee that hoodlums, terrorists, pirates and, possibly, freedom fighters will use it for many years after the Russians have given it up. Still, it might break the old man's heart to know that his invention will no longer protect his homeland.