Echoes of Douglas MacArthur, 9/11 and 'thunder runs' will resonate when the 3rd Infantry Division and 42nd Infantry Divisions deploy to Iraq early next year. These history—laden units will make their own new history. They will be the first unites embodying the ongoing US Army transformation to serve in a combat zone. Secretary of Defense Rumsfeld's vision is proving itself valid in the process.

It was then—division chief of staff Colonel Douglas MacArthur, who in 1917 coined the phrase from which the 42nd takes its nickname. Referring to the fact that it was comprised of National Guard Soldiers from 26 states, he said: 'This division stretches across the land like a rainbow.' 

Today's New York—based Rainbow Division consists of National Guard units from 6 states.  During the 9/11 attacks, four of its battalions were the first military personnel on the scene and  division commander Major General Joseph J. Taluto headed up the National Guard's Joint Task Force response to the crisis.

To this day 42nd officers and Soldiers are proud of their salute and salute response words: 'Rainbow,'  'Never Forget.' 

The 3rd ID, which served during WW1 with the 42nd, led the charge to Baghdad in Operation Iraqi Freedom.  Along the way, spearheading elements such as 2nd and 3rd Battalions, 69th Armor, conducted successful 'thunder runs' that cut their way through enemy positions using the speed and firepower of M1 Abrams tanks.  It will be relieving the 1st Cavalry Division in Baghdad.

Even as operations in Afghanistan and Iraq have proceeded, the  Pentagon's policy of transformation, under Defense Secretary Donald Rumsfeld, is being implemented.  Supervised by Chief of Staff General Peter J. Schoomaker, the US Army has, among other tasks, been developing Soldiers with the warrior ethos and re—balancing force structure with a mix of active and reserve components.  Given the fact that these difficult changes are being accomplished while the global war on terror is being conducted, General Schoomaker has likened the work to 'tuning a car while the engine is running.'   Nevertheless, transformational goals are being achieved.

The 42nd ID will be the first National Guard division to serve in Iraq and will be relieving the Big Red One 1st Infantry Division.  Maj. Gen. Taluto will command units such as the Idaho 116th Brigade Combat Team (or Unit of Action) and Tennessee's 278th Regimental Combat Team. Representing yet another transformational goal, he will also command the 1st and 3rd Brigade Combat Teams of the 3rd ID. The military jargon for that switching of divisional components is the 'plug and play concept,' signifying the capability of fully—trained modular Units of Action to serve wherever and however they are needed. 3rd ID commander, Major General William Webster will then pick up a brigade from the 1st Armored Division and the Louisiana National Guard's  256th Infantry Brigade (Mechanized).

As with previous deployments, groups of officers and senior NCOs from the incoming unit travel to Iraq for 'scouting and reconnaissance' missions, meeting with counterparts whose duties they'll soon be assuming in what is called 'relief in place.' 

For several months now, Soldiers from the 116th, 278th, and 2nd and 3rd Battalions 69th Armor, for instance, have gone to 1st ID headquarters in Tikrit for briefings on their areas of operations, and information on local customs,  the tribes in various provinces, supply routes, etc.  Big Red One veterans share their knowledge of enemy capabilities, his tendencies and lessons learned from his several methods of attack.  The visiting officers and NCOs then join their counterparts to ride convoys, go on patrols and meet with Iraqi leaders in cities and villages. 

Early in December Maj. Gen. Taluto and other 42d ID leaders held a major relief—in—place rehearsal at the 1st ID's Forward Operating Base Danger in Tikrit. 1st ID commander, Major General John Batiste, while urging the 42d to use force whenever necessary against the enemy, stressed that the goal should be to end the violence because most Iraqis want peace.  He then suggested that Rainbow Division commanders trust their line unit subordinates.  'Allow them to make mistakes and let NCO business be their business.'

For his part, Maj. Gen. Taluto, on his fourth visit to Iraq, said that 'Our reconnaissance has been constant and consistent. I think it's been worth every effort. We owe a real debt to the 1st Infantry Division for the wonderful way it has received us. It has been professional in every sense of the word.'

By next March, the transformation will be complete.  The 42nd ID's Task Force Liberty with its veterans of 9/11 and the 3rd ID with its veterans of Operation Iraqi Freedom will be in place, carrying on the noble cause of helping to ensure stability, security and democracy in Iraq.

John B. Dwyer is a military historian.