This is known as divide and rule, a strategy as old as imperialism. It will allow the Americans - they hope - to reassert control over a region they "lost". Other countries, such as Pakistan and the neighbouring former Soviet republics, are being bribed into submission. The "war on terrorism", with its Rambo raids, is merely a circus for the folks back home and the media.

It takes me back to the 1980s when Margaret Thatcher announced there were "reasonable" Khmer Rouge. The aim was to bolster a Khmer Rouge-led coalition, in exile, which Washington wanted to run Cambodia and so keep out its recent humiliator, Vietnam, and the influence of the Soviet Union. The SAS were sent to train Pol Pot's killers in Thailand, teaching them how more effectively to blow people up with landmines. They got on so well together that when the United Nations finally turned up, the Khmer Rouge asked for their old British comrades to join them in the zones they controlled. The same thing may happen in Afghanistan when the UN turns up as the facilitator for America "building" an obedient regime.

Among the international relations academics who provide the jargon and apologetics for Anglo-American foreign policy, divide and rule is known as "containment". The aim is to destroy the capacity of nations to challenge US dominance while allowing their regimes to maintain internal order. The nature of the regime is irrelevant. Thus, people all over the world have been divided, ruled and "contained", often violently: the destruction of Yugoslavia is a recent example; the territory administered by the Palestinian Authority is another. Real reasons for the actions of great power are seldom reported. A morality play is preferred. When George Bush Senior attacked Panama in 1990, he was reportedly "smoking out" General Noriega, "a drug runner and a child pornographer". The real reason was not news. The Panama Canal was about to revert to the government of Panama, and the US wanted a less uppity, more compliant thug than Noriega to look after its interests once the canal was no longer officially theirs.

Likewise, the real reason for attacking Iraq in 1991 had little to do with defending the territorial sanctity of the Kuwaiti sheikhs and everything to do with crippling, or "containing", increasingly powerful, modern Iraq. The Americans had no intention of allowing Saddam Hussein, a former "friend" who had developed ideas above his imperial station, to get in the way of their plans for a vast oil protectorate stretching from Turkey to the Caucasus.

Undoubtedly, a primary reason for the attack on Afghanistan is the installation of a regime that will oversee an American-owned pipeline bringing oil and gas from the Caspian Basin, the greatest source of untapped fossil fuel on earth and enough, according to one estimate, to meet America's voracious energy needs for 30 years. Such a pipeline can run through Russia, Iran or Afghanistan. Only in Afghanistan can the Americans control it.

Also, stricken Afghanistan is an easy target, an ideal place for a "demonstration war" - a show of what America is prepared to do "where required", as the US ambassador to the United Nations said recently. The racism is implicit. Who cares about Afghan peasants? No Paul McCartney concert for them. Moreover, people can be sprayed with bomblets that blow the heads off children, and we in the west are spared, or denied, the evidence. It is clear that most of the media are suppressing horrific images, as was done in the Gulf slaughter. With honourable exceptions, the coverage is, as ever, the opposite of Claud Cockburn's truism: "Never believe anything until it is officially denied." The Sunday papers carry little more than fables straight from the Pentagon and the Ministry of Defence. Talking up a land invasion is an important media task, as it was in the Gulf and Yugoslavia. Talking up Iraq as a source of the anthrax scare, and the next target, is another. Mark Urban, Newsnight's diplomatic correspondent, told Jeremy Paxman recently that the Americans were studying "secret information" that Saddam Hussein was about to "fire off a missile". Evidence? Urban said nothing; Paxman did not press him.

There is no "war on terrorism". If there was, the SAS would be storming the beaches of Florida, where more terrorists, tyrants and torturers are given refuge than anywhere in the world. If the precocious Blair was really hostile to terrorism, he would do everything in his power to pursue policies that lifted the threat of violent death from people in his own country and third world countries alike, instead of escalating terrorism, as he and Bush are doing. But these are violent men, regardless of their distance from the mayhem they initiate. Blair's enthusiastic part in the cluster bombing of civilians in Iraq and Serbia, and the killing of tens of thousands of children in Iraq, is documented. The Bush family's violence, from Nicaragua to Panama, the Gulf to the death rows of Texas, is a matter of record. Their war on terrorism is no more than the continuing war of the powerful against the powerless, with new excuses, new hidden imperatives, new lies.

The problem for people in the west who do not see the violence of Bush and Blair and their predecessors is that they cannot appreciate the reaction. "We have sown the wind; he is the whirlwind," wrote Jean-Paul Sartre in his preface to Frantz Fanon's The Wretched of the Earth, "and all that is stirred up in them is a volcanic fury whose force is equal to that of the pressure upon them [and] the same violence is thrown back upon us as when our reflection comes forward to meet us when we go towards a mirror."

The great people's historian Howard Zinn, Boston University professor and former Second World War bomber pilot, helps us to understand this in his new book, Howard Zinn on War. The attack on the twin towers in New York, he writes, has a moral relation to American and Israeli attacks on the Arab Middle East. If the actions of the west's official enemies receive enormous attention as terrorist atrocities while the terrorist atrocities of the US and its allies and clients are starved of political and press attention, "it is impossible to make a balanced moral judgement", to find solutions to the cycle of revenge and reprisal and to address the underlying issue of global economic inequality and oppression.

Propaganda is the enemy within. "By volume and repetition", a barrage of selective, limited information is turned out by tame media, information isolated from political context (such as the bloody record of the superpower throughout the world). In the absence of alternative views, it is no surprise that people's "reasonable reaction" is that "we must do something". This leads to the quick conclusion that "we" must bomb "them". And when it is over, and the corpses are piled high, "only Milosevic stands in the dock, not Clinton. Only Saddam Hussein is outlawed, not Bush Senior. Only Bin Laden has a $50m price on his head, not Bush Junior and his predecessors." It is, says Zinn, "a tribute to the humanity of ordinary people that horrible acts must be camouflaged [with words] like security, peace, freedom, democracy, the 'national interest'."