military operation since the 1991 Persian Gulf war, and may have implications for variousdefense programs of interest to Congress. It will beupdated periodically as new information becomes available. Deriving "Lessons" of the War: Some Cautionary Notes

Although the Department of Defense (DoD) and other organizations customarily produce "lessons learned" reports following the conclusion of a major military operation like the Iraq war,this report for the most part avoids using the term "lessons" because it can imply the making ofrecommendations - something that CRS reports do not do. These include the following:
Information is imperfect; early lessons are subject to change. Public information about the Iraq war is currently incomplete, and will likely remain so for some time. Each war is unique; avoid "overlearning" the lessons of this war. In evaluating purported lessons offered by various sources, one factor to consider is whether thosesources have a potential financial, institutional, or ideological stake in the issue. These conclusions and speculations, if correct - and not all observers agree with them (6) - are potentially ofgreat significance to Congress, for at least two reasons:
Implementing the Administration's vision for defense transformation could substantially affect the composition of U.S. defense spending, shifting defense funding towarddefense programs that are judged to be transformational and away from defense programs that arejudged to be non-transformational or "legacy." The Administration may be encouraged to invoke the theme of transformation to help justify or seek rapid congressional consideration of legislative proposals affecting DoD thatmay or may not be transformational, depending on one's definition of transformation, includingproposals which could, if implemented, affect Congress' role in conducting oversight of U.S. defenseactivities. The administration's military strategy is sometimes called the 1-4-2-1 strategy because it calls formaintaining U.S. military forces sufficient for:
[1] "protect[ing] the U.S. domestic population, its territory, and its critical defense-related infrastructure against attacks emanating from outside U.S.borders,"
[4] "maintaining regionally tailored forces forward stationed and deployed in[the four regions of] Europe, Northeast Asia, the East Asian littoral, and the Middle East/SouthwestAsia to assure allies and friends, counter coercion, and deter aggression against the United States,its forces, allies, and friends,"
[2] "swiftly defeating attacks against U.S. allies and friends in any two theatersof operation in overlapping timeframes," and
[1] "decisively defeating an adversary in one of the two theaters in which U.S.forces are conducting major combat operations by imposing America's will and removing any futurethreat it could pose. Prior to the Iraq war, those who were concerned about whether U.S. forces were sufficiently sized to carry out this strategy pointedto the high operational tempo that certain parts of the military have maintained in recent years, thelarge number of reserve forces that have been activated since the terrorist attacks of September 11,2001 (and the extended length of certain reserve-unit tours of duty since that time), the interestamong certain Army officers for increasing the Army's active-duty end strength so as to bettersupport ongoing commitments in various locations, gaps in forward deployments of Navy ships tocertain overseas regions, and the relationship of the total number of active air wings, divisions, andships to the potential requirements of fighting two regional wars in overlapping time frames. (26)
Post-War Debate. forces than currently planned. Iraq War. (32)
Some observers believe the experience with base access during the Iraq war may lead to increased interest in a new operational concept (i.e., a new approach to warfighting) referred to assea basing, or more formally as enhanced networked sea basing. One of the most significant defense-program debates going into the Iraq war - and potentially one of those mostsignificantly influenced by the war - concerns the future size and composition of the active-dutyArmy. Number of Active-Duty Army Divisions. Plan to Shift to Lighter Forces. Combat Aircraft Operations in the Iraq War. Bomber supporters could argue that the Iraq war and the war in Afghanistan demonstrated that the value of bombers in combat operations has been significantly enhanced by the advent ofprecision-guided weapons. Combat-Support Aircraft. (122)
Urban Combat in the Iraq War. (131)
Types of Friendly Fire Incidents. The Iraq war appears to have highlighted certain questions about the analytical effectiveness of U.S.intelligence agencies. The Iraq war may have implications for specific air mobility program issues, including the following. Future Airlift Technologies.
The recent war against Iraq may have implications for various defense programs of interest to Congress. This report surveys some of those potential implications, and will be updated periodicallyas new information becomes available. Three cautionary notes associated with post-conflict"lessons-learned" reports apply to this report: Information about the Iraq war is incomplete andimperfect, so early lessons are subject to change. Each war is unique in some ways, so observersshould avoid "overlearning" the lessons of the Iraq war. And potential U.S. adversaries can derivelessons from the Iraq war and apply them in future conflicts against U.S. forces, possibly devaluingU.S.-perceived lessons. It can also be noted that some persons or organizations offering purported lessons of the Iraq war may have a financial, institutional, or ideological stake in the issue.
Many observers have concluded that the Iraq war validated the Administration's vision for defense transformation, or major parts of it. Other observers disagree. The issue is potentiallysignificant because implementing the Administration's vision could affect the composition of U.S.defense spending, and because the Administration may invoke the theme of transformation to helpjustify or seek rapid congressional consideration of legislative proposals, including proposals thatcould affect Congress' role in conducting oversight of defense programs. The Iraq war mayinfluence debate on whether active-duty U.S. military forces are sufficiently large to carry out currentU.S. military strategy, and on whether greater emphasis should be placed on forces that are lessdependent on access to in-theater bases.
One of the most significant defense-program debates going into the Iraq war - and potentially one of those most significantly influenced by the war - concerns the future size and composition ofthe active-duty Army. Both supporters and opponents of maintaining at least 10 active-duty Armydivisions may find support in the Iraq war for their positions, as may both supporters and opponentsof the current Army plan to shift toward a mix of fewer heavy armored units and a larger number oflighter and more mobile units.
The Iraq war validated the effectiveness of combat-aircraft armed with precision-guided weapons, and may influence discussions about current plans for investing in specific aircraft andmunitions programs. The Iraq war may reinforce support generated by the war in Afghanistan forincreased investment in U.S. special operations forces. It may also highlight questions concerningreserve combat divisions and the potential consequences of extended callups of large numbers ofreserve forces.
The war appears to have demonstrated the value of network-centric operations and timely battlefield intelligence, and the potential value of psychological operations. It appears to haveconfirmed the importance of preparing for urban combat. The war offered a limited real-world testof the Patriot missile defense system. The war may lead to renewed discussions about strategies forreducing friendly fire incidents. It may reinforce support for investing in aerial refueling capabilities,and increase interest in potential new airlift and sealift technologies.