The only place that allegory falls apart is Saruman's overwhelming force against a weaker Rohan. The overwhelming force is clearly ours, though we share none of the goals. We are the battle of Helm's Deep as it should have been perhaps... Taking out the evil before it can become strong. It is an imperfect allegory, to be sure. They, however, are Orc-Kind, of this there can be no doubt, and there are buttloads more of them where those came from. Actually, it scares me a little that the allegory may be closer to the truth than we yet know.