This thesis examines the contribution of the Private Military and Security Industry (PMSI), as an element of the United States (US) total force, to the US military capability in pursuing Phase IV Operations in Iraq from 2003 until 2011. In order to do so, the study proposes a typology of five types of contribution categories which define the link between the ends demanded by the US government (strategic goals) and the use of the PMSI as a tool to help achieve them. By incorporating a model from the operations management field, the Hayes and Wheelwright's Four-Stage model, this thesis identifies the categories of Assistant, Implementer, Crucial Supporter, Driver, and Spoiler as distinct forms of engagement, constituting a framework for the assessment of the nature of the relationship between the contractors’ activities and the strategic goals they sought to help achieve. Applied to the case studies of armed private security services and base support services, this framework reveals that contractors became the Crucial Supporter of the US military efforts in Phase IV Operations in Iraq. In the aftermath of the ill-planned regime-change, followed by unforeseen operational circumstances on the ground, and constrained by the US domestic policy reservations towards prolonged nation-building efforts, the US government found both armed security contractors and base support contractors to be a critical asset of the US military strategy on the ground. Through their constructive contribution towards the size of the deployable force, the available timeframe, the objectives and the strategic goal of these operations, they became a key partner of the US military efforts in Iraq. Utilising a descriptive and exploratory approach, and relying on a range of sources, including official documents, semistructured interviews and publicly available video testimonies of US veterans from Iraq, this thesis highlights the PMSI’s strategic value in a complex expeditionary operation while providing a detailed insight in the complexity of modern warfare.

The Vietnam War was one of the most traumatic events ever to afflict the US Military. From the ashes of this defeat, the US Military sought to renew itself. As part of this process of renewal, the US Army in particular engaged in serious soul searching as to how, and under what circumstances, the United States ought to commit itself to war. The answers that were derived from this soul searching are known collectively as the Powell Doctrine, named after General Colin L. Powell, Chairman of the Joint Chiefs of Staff (1989-1993). The elements of the Doctrine are as follows: the need for “overwhelming” force; the need for public and Congressional support; the need for clear objectives; the need for a clear “exit strategy”; and force should only be used in the “vital national interest.” This thesis will advance four principal arguments: first, that the evolution of the Powell Doctrine cannot be understood without reference to the US experience in Vietnam; second, that the various elements of the Powell Doctrine have a logical relationship to one another which means that the Doctrine as a whole should be considered as a single, integrated body of thought; and, third, that Colin Powell, in his Foreign Affairs article, is simply giving public articulation to an intellectual climate that had already become influential before his ascent to the Chairmanship of the Joint Chiefs of Staff. And that, whilst the Powell Doctrine does deserve to be called a doctrine in the military sense of the word, this is not a full explanation of the conditions Powell has laid down as they encroach upon profoundly political issues. And thus, whilst the Powell Doctrine does deserve the title “doctrine,” it is also an attempt to formulate a coherent set of principles to inform US “National Security” policy in areas that go beyond those traditionally seen as being of military concern.

This thesis examines the British Commonwealth and Allied Naval forces operation on the west coast during the final two and a half years of the Korean War, particularly focused on their co-operation with the anti-Communist guerrillas. The purpose of this study is to present a more realistic picture of the United Nations (UN) naval forces operation in the west, which has been largely neglected, by analysing their activities in relation to the large number of irregular forces. This thesis shows that, even though it was often difficult and frustrating, working with the irregular groups was both strategically and operationally essential to the conduct of the war, and this naval-guerrilla relationship was of major importance during the latter part of the naval campaign. It concludes that, to the British Commonwealth Commanders and Allied Naval forces on the west coast, a large part of the relationship with the guerrillas during the Korean War could be explained as that involving a compelled co-operation with unreliable partners.