V: Prudence (defined as carefully weighing political options; see Morgenthau)I'll start by explaining what realism isn't, and what it is, and then how to use it in an LD round, not just for this particular topic.
C: Political realism
The idea here is that nations act in their best interests, independent of overarching moral considerations, charting a careful course in a chaotic, Hobbesian world. Justice isn't a proper description of international relations, so the resolution is a category error, analogous to claiming that numbers are too heavy, or colors are too fearful. (Be aware that some judges hate political realism. I mean really, really hate it.) Realism can also be turned, potentially, in the way the Social Contract argument can be turned, if realism is discussed in terms of its consequentialist impacts, rather than in its inherent approach.
If you believe that states are inherently moral agents--or that the people who make decisions for states are moral agents, regardless of whether states themselves are moral--you are not a realist. Instead, you're a political moralist. There are several ways states might have moral obligations: there might be some objective moral law that all states ought to follow, or there might be contractual obligations (treaties, alliances, international law, etc.) that have actual normative force.
Regardless of the efficacy or enforceability of these norms, a political moralist believes they are real, and ought to guide and constrain state actions.
Whether these obligations are positive (i.e., states should act in certain ways to achieve specific ends), or negative (i.e., states should refrain from acting in certain ways), is another question.
In contrast, if you believe that states are not inherently moral agents--and that the people who make decisions for states do not need to concern themselves with traditional morality when making political decisions--you are a political realist. States are only interested in preserving their own power in an anarchic system, and must often make difficult decisions that would not survive scrutiny in a traditional system of ethics. As Hans Morgenthau writes,
Realism maintains that universal moral principles cannot be applied to the actions of states in their abstract universal formulation, but that they must be filtered through the concrete circumstances of time and place. The individual may say for himself: "Fiat justitia, pereat mundus (Let justice be done, even if the world perish)," but the state has no right to say so in the name of those who are in its care. Both individual and state must judge political action by universal moral principles, such as that of liberty. Yet while the individual has a moral right to sacrifice himself in defense of such a moral principle, the state has no right to let its moral disapprobation of the infringement of liberty get in the way of successful political action, itself inspired by the moral principle of national survival. There can be no political morality without prudence; that is, without consideration of the political consequences of seemingly moral action. Realism, then, considers prudence--the weighing of the consequences of alternative political actions--to be the supreme virtue in politics. Ethics in the abstract judges action by its conformity with the moral law; political ethics judges action by its political consequences.Note that Morgenthau doesn't deny the existence of morality overall; rather, he claims that the good--defined as rational aims successfully carried out--is the aim of statecraft, not the right. Prudence, not justice, is the goal; success, not virtue, is the measure of action.
This view traces back to Thucydides, who Morgenthau name drops; Machiavelli, who applied it in his classic text The Prince; and Thomas Hobbes, who developed the idea of a "warre of all against all" in the state of nature. Contrasted with these three, Morgenthau is actually the least controversial and least cynical in its view of human nature.
As I described above, judging state actions in moral terms, in the realist view, is a "category error." Morgenthau again:
This realist defense of the autonomy of the political sphere against its subversion by other modes of thought does not imply disregard for the existence and importance of these other modes of thought. It rather implies that each should be assigned its proper sphere and function. Political realism is based upon a pluralistic conception of human nature. Real man is a composite of "economic man," "political man," "moral man," "religious man," etc... Recognizing that these different facets of human nature exist, political realism also recognizes that in order to understand one of them one has to deal with it on its own terms.In other words, our decisions in different contexts are made with different considerations--and, in Morgenthau's (controversial) rendition, no single role trumps all others. The political is the political, and nothing more.
Using Political Realism in a Debate Round
As Morgenthau argues, the supreme virtue of political realism is prudence: treading cautiously in a dangerous world. You may set that up as your value, and political realism as your criterion, if you're using this line of argument. However, you might also value truth or reality, and have a criterion of "properly assigning responsibility," if you view the resolution through a truth-testing lens.
For the humanitarian aid resolution, either will work; the point is that states are held to a different standard than individuals.
Even if they aren't, state actions are contextual and situated, which means that realism is a perfect counter to Kantian (or any other) absolutism.
Defeating Political Realism
Realism doesn't necessarily have a good answer for the inherent worth of actions bad states might take. If states should act pragmatically in their own interests, what if such actions are, from a moral standpoint, evil? This question may have a good answer within the realist framework, but it's difficult, and the strong biases of some judges against realism may make it a losing issue. One of my debaters had a judge who described his sentiments thusly: "I'll go barf in a bucket, then vote Neg."
Realism might also be wrong, for several reasons. First, if Morgenthau is wrong about human nature, then the whole philosophy collapses. In other words, it might be that "political man" is no different from "economic man" and "moral man." There's only humanity, which can't be contextualized or situated away.
Second, if the global political system truly isn't anarchic--witness the rise of international law and human rights norms--then there is a global contract that supersedes (or at least equates with) individual contracts between states and their citizens. In Morgenthau's time, such norms and contracts may have seemed as thin as tissue, but in the 21st century, they seem to have strengthened. (If Russia ends up successfully occupying Crimea and destabilizing Ukraine, I take it all back.)
For Further Reading
"Political Realism in International Relations"
"The New New World Order"