Despite defeat in the 1991 Gulf War, Iraq remains one of the largest military powers in the Middle East region.
But its potency has been severely undermined by more than a decade of sanctions, an arms embargo, and US and UK bombing.
Most regular Iraqi soldiers are conscripts
"Iraq's inability to modernise means that much of its armed forces are now obsolete. Many units have uncertain readiness, and will be difficult to sustain in combat," a 2002 study by the Centre for Strategic and International Studies (CSIS) reported.
Despite numerical superiority in the region, most military analysts say that Iraq's forces would stand no chance against the United States, the most advanced military power in the world.
The Iraqi army is usually divided into two groups; the regular army and the Republican Guard.
Iraq has about 375,000 regular soldiers. These men - mainly conscripts - are poorly equipped and paid. Morale is believed to be low and it is widely predicted that many units would quickly surrender in the face of any US attack.
Iraq is a highly ethnically diverse country, and these divisions extend into the armed forces. Saddam Hussein has had to deal with extensive problems within his military over the last decade, according to reports.
Iraq is estimated to have about 2,600 tanks, mostly ageing Soviet T-55, T-59 and T-69 designs imported or built under licence.
There are a similar number of armoured personnel carriers of various types. Only a comparatively small number of these vehicles are thought to be operational.
All of Iraq's military hardware suffers from a shortage of spare parts.
Iraq's patched-up tanks are expected to provide little opposition to the US
Fuel shortages restrict their operability, and many tanks are reportedly in such poor state that the army is resigned to simply placing them in position and using them as artillery.
Any tanks which make it into action are predicted to have little effect against modern, technologically advanced US armour. Those that do are likely to be swiftly picked off by the US' overwhelming aerial firepower.
The Republican Guard is considered Iraq's most effective fighting force. With a manpower of 60-70,000 men and run by Saddam Hussein's younger son, Qusay, its units are dedicated to defending and protecting the regime.
Recruits are usually volunteers and are often from Saddam Hussein's home town Tikrit. They are better trained, equipped and paid than their regular army counterparts.
Republican Guard units have the most modern types of tanks - the Russian-designed T-72, some of which are equipped with night-vision equipment.
The Iraqi air force is also run down, with few modern aircraft and poorly trained pilots. Estimates of the numbers of serviceable planes range from 100-300.
Fuel shortages have prevented pilots from gaining sufficient flying experience to be able to fight effectively in the air. Iraq still has extensive stocks of short-range air-to-ground missiles and cluster bombs, analysts believe.
US warplanes are the most advanced in the world
Roughly 17,000 personnel are thought to serve in Iraq's air defence command, which controls some 850 surface-to-air missile launchers and about 3,000 anti-aircraft guns.
Iraq is believed to have about a dozen al-Hussein missiles which have a range of 650km, enough to reach cities in Israel, Turkey, Kuwait and Saudi Arabia.
Some experts believe they could be fitted with chemical or biological warheads. Most analysts agree that Iraq would require several years and possibly help from a foreign power to produce longer range missiles.
A number of smaller, shorter range al-Samoud missiles have recently been handed over to and destroyed by UN weapons inspectors.
In modern warfare, military spending is a far better indicator of military might than sheer numbers of tanks, troops or aircraft, analysts say.
The US position as the world's only superpower effectively guarantees its military pre-eminence.
Washington will spend $343bn on its armed forces in 2003.
The combined military budgets of the "axis of evil" identified by President George Bush last year - Iran, Iraq, and North Korea - comes to a about $10bn.
Russia and China's military expenditure totals $95.5bn.
In contrast to Iraq's dilapidated weapons, the US has an array of versatile and modern equipment. In terms of manpower its armed forces are not only large, but well equipped, trained, supported and motivated.
On the ground, its main M-1 Abrams battle tanks are fast across the ground and packed with the latest electronic targeting and night vision technology.
In the air US warplanes are the world's most advanced, with the ability to patrol the skies 24-hours a day and perform a multitude of missions ranging from close ground support to high-altitude bombing.
Both above and below the ocean surface fleets of giant Nimitz class aircraft carriers and nuclear submarines give Washington the ability to extend its massive firepower to any point on the globe.
In support of these forces, the US is unrivalled in its communications, intelligence gathering, and logistics networks.