Resolved: The United States is justified in using private military firms abroad to pursue its military objectives.The following list of Value and Criterion pairs is neither conclusive nor comprehensive. Rather, it's a set of suggestions to spark your thinking. Feel free to share your bright ideas, constructive criticism, and questions in the comments.
A work in progress.
V: National Security
C: Pragmatism / Bolstering defense forces
We ought to value national security because the resolution concerns whether PMFs can reasonably or legitimately be used to attain military objectives. Hence the oft-used "toolbox" metaphor: to maintain security, we have to keep all the necessary tools at our disposal. Limiting our options could be expensive, counterproductive, or disastrous to our military efforts. This position will likely clash with advocacies based on freedom or human rights, since valuing security as paramount tends toward oppression.
V: National Security and/or International Stability
C: Preserving Hegemony
If PMFs help the U.S. maintain military superiority and economic clout--and thus the global balance of power via American hegemony--then they're warranted. The hegemony argument suffers from a couple pitfalls: first, it may not be true (in a multipolar world full of dangerous nonstate actors and nontraditional, asymmetrical conflict, can the U.S. even stake claim to be a hegemon?), and second, even if it's true, whether hegemony is good is another matter entirely--racism, ethnocentrism, or patriarchy, anyone? Benevolence is often solely in the eye of the benefactor.
V: Prudence (defined as carefully weighing political options; see Morgenthau)
C: Political realism
The idea here is that the US must act in its best interests, which are independent of overarching moral considerations. Rather, the U.S.'s goal is to preserve its own power, charting a careful course in a chaotic, Hobbesian world. Realists generally denounce grand state-building / democracy-spreading schemes, however, so there may be a "turn" available: that realism demands a massive scaling-back of American military activity abroad.
V: Justice or Governmental Legitimacy
The Constitution not only provides a justification for national defense, but seems to permit the use of Private Military Firms. So far, I have yet to see a compelling analysis that PMFs are unconstitutional; if you've found one, pass along word.
V: Societal Welfare or National Security
C: Capitalism / Free Market
PMFs, like any other business, provide jobs to hardworking Americans (and foreign nationals). Further, PMFs are constrained by market forces, which keeps them from acting too recklessly or abominably (lest they lose clients). If you're debating in a progressive region and run this type of argument, expect to face the "Cap K."
C: Reducing "Warism," Preventing Future Conflict; Pacifism; Isolationism
Duane Cady describes warism as "the uncritical presumption that war is morally justifiable, even morally required." PMFs incentivize conflict, since they have a financial stake in providing security or goods in war zones. When the war ends, PMFs have to move on to the next opportunity. Eisenhower's warning about the "military-industrial complex" anticipated this sort of perpetual conflict machine.
V: Justice or Morality or Governmental Legitimacy
C: Social Contract
The resolution uses the phrase "is justified," which may be defined in moral terms. The moral obligation of the State is based on its contractual duties and limits--and its monopoly on the legitimate use of force. Subcontracting this to PMFs is a dangerous policy, since PMFs are accountable to stakeholders who may not even be U.S. citizens or have the U.S.'s best interests in mind. In contrast, the U.S.'s citizen-soldiers have strong commitments to the U.S's military objectives; it's the focus of their recruitment, their training, their everyday life, and the entire command structure.
V: Justice or Morality
C: Just War Theory
If PMFs don't meet the criteria of jus in bello, we negate.
C: Reducing the power of the state and/or corporations
The seemingly ever-expanding influence of corporations and states on individuals--and of corporations on states--means that we risk becoming a paternalistic plutocracy that defends its own interests in the guise of national security. Globalization, corporate welfare, financial bailouts... and PMFs, all in an unholy alliance.
V: Justice or Morality or Human Dignity
C: Protecting Human Rights
Thesis: If protecting human rights is essential to justice (or morality), and if PMFs (especially security firms) violate rights with impunity, then we must negate.
Could Go Either Way
V: Societal Welfare (or Morality or Life or National Security)
C: Consequentialism (or Utilitarianism, Act or Rule)
Any case predicated on a body count, a dollar figure, or any other quantifiable metric of success is essentially consequentialist (and perhaps utilitarian). Not that there's anything wrong with that.