With just two days to go before the UN weapons inspectors arrive in Baghdad, George Bush's administration is still beating the war drum. On Thursday night, Donald Rumsfeld, the defense secretary, confidently predicted that, should a war erupt, the Iraqi army would soon surrender in the face of overwhelming US force. He noted that in the first Gulf war, when allied forces pushed Iraq out of Kuwait, ground combat had lasted only 100 hours.

"I can't say if the use of force would last five days or five weeks or five months, but it certainly isn't going to last any longer than that," he said. "It won't be a world war three."

You have always got to hope for minimum loss of life in any war, but Mr Rumsfeld's prognosis about the speed of an Iraqi army collapse is ideologically driven and strategically ill-informed.

In the event of an invasion, US forces will face an army that has been thoroughly indoctrinated, with party commissars in every unit. In addition, a ruthless system of surveillance and constant purges mean that the officer corps has had to renounce political activity to survive. To quote President Saddam Hussein: "With our party methods, there is no chance for anyone who disagrees with us jumping into a couple of tanks and overthrowing the government. These methods have gone."

It is true that Iraqi resistance in the 1991 Gulf war was negligible. The troops that surrendered in their thousands to coalition forces were badly trained, poorly led and had often not been fed for days. The war was a one-sided affair, with the Iraqis overwhelmed by superior weapons, technology and air power.

However, it is often forgotten that the Iraqi leadership made no serious attempt to defend Kuwait City. The fortifications were half-hearted and badly planned. They were primarily designed for propaganda, to convince coalition forces that military liberation would be too costly. Despite the portrayal of a heroic resistance in the "mother of all battles", once the ground war began, President Saddam quickly withdrew most of the republican guard, redeploying them around Baghdad to guard his regime. Substandard and ill-prepared troops were left to face certain defeat.

After the Gulf war defeat, the Iraqi army was cut to less than half its original size. The idea was to create a smaller, more disciplined force, ideologically committed to defending the regime. For more than a decade Washington has looked to this army for regime change. Today, the US government still hopes a coup triggered by an invasion will save American troops the high cost of fighting through Baghdad's streets to reach the presidential palace.

Like Washington, President Saddam is also aware of the dangers the Iraqi armed forces pose to his continued rule. To counter this he has staffed the upper ranks with individuals tied to him by bonds of tribal loyalty or personal history. Like him, most officers are Sunni Arabs, the country's traditional ruling class. They are outnumbered by Shia Muslims and well aware of the resentment towards them.

In addition, members of President Saddam's tribe, the Albu-Nasir, and those hailing from his hometown, Tikrit, dominate the army and security services' command, benefiting from regime patronage and enforcing his rule. They are also more than aware of the anger that will be directed at them if he goes. Because of this, those hoping for a coup may be disappointed. The regime has created a "coalition of guilt" that underpins its continued rule with corruption and great fear about what will happen when it is finally toppled.

Sanctions

In contrast to 1991, the battle this time will be not for a foreign land but for the very survival of a regime many have spent their lives serving. An invading US army will face 375,000 Iraqi troops and 2,200 tanks.

Analysts are right to point out that the army as a whole has suffered greatly during more than a decade of sanctions. Beyond elite regiments, equipment is old and badly maintained. Estimates suggest that the army is only 50% combat effective, and regular troops may well behave as they did in 1991, fleeing the battlefield once war begins. On the other hand, President Saddam has surrounded himself with a robust security system spreading out in three concentric rings. The security services become more disciplined, motivated and reliable the closer they are to the president.

The republican guard makes up the first ring of the regime's security. Stationed on the three main roads to Baghdad, this parallel military force totals between 50,000 and 70,000 men.

They are better paid than ordinary soldiers and much more likely to remain loyal. Many stood by their posts during the Gulf war, losing a third of their tanks. In the aftermath, they played the lead role in suppressing Shia and Kurdish revolts in the north and south of the country.

The next ring of security is the special republican guard, formed in the 1980s when the republican guard became too large to be totally trusted. Consisting of 26,000 men, they are the only troops stationed in Baghdad. The loyalty of this force's officers is beyond doubt. About 80% of them come from the same region as President Saddam, and they have been used as the regime's main tool for policing Iraq.

Finally, surrounding President Saddam and the 50 or so people who rule Iraq are a myriad of competing security organizations. Each one is charged with overseeing the others, and they are headed by a small group of individuals who are keenly aware that their continued health and prosperity is dependent upon the rule of their boss. They too would fight to the last to defend him.

One of the main problems during the Iran-Iraq war was the army's inability to act on its own initiative. To counter this, Baghdad has reportedly decentralized its army command and control down to the lowest level possible. Responsibility for each urban center, from Basra in the south to Mosul in the north, has been delegated to a trusted high-ranking soldier. Each town has been garrisoned with troops, and stockpiles of weapons and food have been built up.

Should hostilities start, martial law would be declared and troops brought on to the streets. The ministry of information has developed a highly efficient press handling system. Once bombing begins, with its inevitable civilian casualties, the hope is that international press coverage will put pressure on Washington to stop the war prematurely, as it did in 1991.

Baghdad will be key. It is within this sprawling city of five million that US troops will have to hunt down the Iraqi dictator and his close associates. With this in mind, all troops and security services loyal to the government will in the last instance be massed in and around the capital.

Caught between a potentially hostile Iraqi population bent on revenge and an invading army committed to regime change, those fighting alongside President Saddam will have little choice but to remain loyal to the end. The result could be the worst-case scenario for US military planners: an organized, committed and disciplined force with nowhere to go, defending a highly populated urban area. In front of the world's media, US troops would have the unenviable task of distinguishing these forces from the wider, innocent, civilian population.

If Mr Bush orders US troops to invade Iraq to topple the regime, it will not only be the most important and risky decision of his presidency, but a momentous event in world politics. The only thing certain about it is that it will not be as simple as Mr Rumsfeld says.

Dr Toby Dodge is an Iraq expert at Warwick University and an associate fellow of the Royal Institute of International Affairs.

© Guardian Newspapers Limited 2002

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