'Yes,' say many observers of the current recruiting crisis and the chaos in Iraq, such as Bob Herbert and Armando at Daily Kos (a site sporting a new, spectacularly ugly design). Sure, the all-volunteer force worked great for the short-term combat of Desert Shield/Storm, but for drawn-out conflicts like the one in Iraq, it's unworkable. The recommendation of Herbert and others is a draft, which would ensure the viability of our armed forces while--and this is a key side-benefit--making it much more difficult for politicians to order our troops into combat. I have a certain amount of sympathy for the idea of a draft that would more equitably spread the pain of conflict among the American people. But the situation in Iraq is hardly a good test of the concept of a volunteer army.
First, because the operations there have been so incompetently planned and executed by the Pentagon, and people inside and outside the military are beginning to see just how bad a cock-up Iraq has been. Who would want to risk their life in an operation run by idiots? Second, the moral case for the war and the sacrifices it requires was never made to the American people. Instead of asking for sacrifice in the service of vital national interests, the Bush administration told us how easy everything would be and asked us to continue shopping. What reasons war supporters gave for beginning the war and occupation have turned out to be at least misguided, some probably out-and-out lies. Given no opportunity to debate the war with a full realization of its potential costs, groping for information about the dangers of action or inaction in an environment intentionally clouded by thick clouds of half-truths and spin, it's hardly surprising that Americans are not more willing to risk their lives, and those of ones they love, in Iraq.
Whether or not an all-volunteer force can fight a long just war, run w/ reasonable competence, fought in defense of truly vital national interests, and entered into only as a last resort after a full and fair debate over the war's merits, remains to be seen. (The historical evidence is mixed, I would say: numbers of volunteers tailed off markedly after the first years of the Revolutionary War, and the Civil War; in World War II a draft was swiftly implemented, even as plenty of volunteers presented themselves as well.) Iraq tells us only that an all-volunteer force will find it difficult to sustain a long-term combat commitment entered into without a full debate, with constantly shifting goals, with poor planning and incompetent leadership, and with only a hazy notion of the vital national interests at stake.