An increase in the number of US troops is unlikely to bring about any substantial improvement, writes Tom Clonan
Taken in context, the numbers of US troops in Iraq are quite low. In 1991, during Operation Desert Storm, the US general staff deployed more than half a million US troops to achieve a relatively straightforward military objective - to expel Saddam Hussein's forces from Kuwait.
In 2003, at the insistence of secretary of defence Donald Rumsfeld, the US military was confined to a tiny invasion force of 175,000 - described by US generals as Rumsfeld's "Invasion-Lite" scenario - to decapitate Saddam's regime and achieve the highly complex military task of nation-building.
Four years later, President Bush's decision to send an extra 21,500 soldiers to an anarchic and chaotic Iraq brings to mind the American expression of "being a dollar short and a day late".
President Bush's latest military initiative for Iraq is already under way with the 2nd brigade, US 82nd airborne preparing to deploy immediately to Baghdad from Kuwait. A further four combat brigades will rotate into Baghdad on an ongoing basis over the coming months.
The Iraqi capital is currently under the nominal control of the US 1st cavalry division from Fort Hood, Texas. As President Bush's proposal for a troop "surge" in Iraq is rolled out, he will have reinforced his fellow Texans in Baghdad by a total of 17,500 combat troops by late spring.
Two US marine corps regiments totalling 4,000 troops will also be deployed to reinforce the US 1st marine expeditionary force currently engaged in combat with the increasingly problematic Sunni insurgency in al-Anbar province.
This twin-tracked proposal will bring the total number of US troops in Iraq to approximately 161,000 by early summer - the highest number of US personnel in-theatre since a peak of 175,000 during the invasion in March and April of 2003.
The task facing the Texas-based 1st cavalry division in Baghdad is daunting. With reinforcements numbering a mere 17,500 troops, they will be expected to pacify a city with a population of approximately six million Shia and Sunni citizens divided by seething sectarian hatred.
Sectarian tensions in Baghdad have reached civil war proportions in recent months with a US military assessment concluding that 80 per cent of Iraq's medium-intensity conflict is currently being fought within the capital.
Attempts to pacify restive Iraqi cities by "surging" or concentrating US troop numbers are not without precedent. In the spring and winter of 2004, US troops were concentrated around the city of Falluja in order to conduct two separate offensive operations against Sunni insurgents located there.
During both offensives US troop losses rose to record monthly highs of 135 killed in action in April 2004 and 137 killed in action in November 2004 - more than twice the monthly totals killed during the initial high-intensity invasion period of March and April 2003.
Despite these spikes in US losses - and increases in Iraqi civilian casualties - the Sunni insurgency in Falluja and al- Anbar province remained largely intact after the marine corps operations of 2004, with no medium or long-term improvements in stability.
Based on these experiences, an objective military analysis would hold that the deployment of 17,500 US combat troops to a city as large as Baghdad might similarly simply result in an increase in US combat casualties with no real peace or security dividends in prospect for ordinary Iraqis.
Prior to President Bush's most recent announcement on his military plans for Iraq, US armed forces were stretched to near breaking point due to mounting overseas commitments. As of January 2007 the Americans have lost almost 35,000 combat troops to death and serious injury on the battlefield in Iraq.
Arising from these casualty figures, America's relatively small all-volunteer army has suffered an attrition rate close to 16 per cent in Iraq - almost twice that of Vietnam's attrition rate of 9 per cent.
With no draft to rely on, the US president with his latest initiative is committing 75 per cent of the US military's total of 33 combat brigades to Iraq with no clear mission statement or set of realistic objectives or exit strategy.
As the war in Iraq rumbles on into its fourth year - making it a more prolonged military commitment than US involvement in the second World War - the US general staff will be concerned that a relatively light occupation force of some 161,000 troops will become ensnared by osmosis and mission creep into Iraq's civil war.
President Bush's last-ditch strategy to save face - by bolstering a force of beleaguered Texan troops in Baghdad - may amount to a military operation similar to the Alamo in more ways than one.
Tom Clonan is Irish TimesSecurity Analyst. He lectures in the School of Media, DIT