Multiple deployments, extended tours, flagging enlistment and retention rates—all are signs of a military that is over-extended.

The challenges presented to America's downsized military in Iraq and Afghanistan raise serious questions about our future capacity to engage in other parts of the world where our national interests are at stake. Opportunists abound, and there are a number of nations (Iran, North Korea, China and Russia, to name a few) who are capable of, and likely to create, mischief while our attentions are focused on fighting terrorism in Iraq and Afghanistan.

These concerns inevitably give rise to questions about the adequacy of the size of America's military. There are legitimate questions about our existing strength levels that we simply must come to grips with. Failure to deal with these issues could be disastrous. One reason we continue to avoid the subject, however, is because such questions invariably lead us to another question that most politicians do not want to confront—whether there is a need to resume the draft.

From a political standpoint, the draft is like social security. It is the third rail of politics. Touch it and you die. That's why Congressman Charley Rangel's bill to bring back the draft was a non-starter in the Congress. Who wants to see their political career founder on the shoals of involuntary military conscription? Therefore, as with social security, Congress would rather engage in arcane debates about the numbers than grasp the nettle and do something about the underlying problem.

I'm not a military expert or statistician, so I can't shed any light on the numbers controversy. Nevertheless, it seems to me that there are two important words that warrant serious consideration in evaluating whether or not we should bring back the draft. Those words are "public sentiment." Abraham Lincoln recognized the importance of public sentiment in shaping public policy when he observed: "In this and like communities, public sentiment is everything. With public sentiment, nothing can fail; without it, nothing can succeed."

The truth of Lincoln's observation was manifestly apparent during the Vietnam War era. At that time, young men between the ages of 18 and 26 were eligible for the draft. Many had moral reservations about America's involvement in Vietnam, or at least felt the war had dubious justifications. Because they themselves were draft eligible, they and their friends (and often their families) mobilized to express their opposition to the war. "Hell no, we won't go!" became their mantra. Hundreds of thousands gathered from across the country to express their opposition to the war. The protestors' passion was fueled, in no small part, by the fact that they themselves were at risk of being deployed to fight, and possibly die, on a foreign field. The notion that they might be required to die for a cause they deemed unjust was abhorrent to them. They took the matter personally because they themselves had "skin in the game." Hence, Muhammad Ali's immortal line when he resisted the draft, "I ain't got nothing against the Viet Cong." The anti-war movement changed the course of America's policy in Vietnam, because it mobilized public sentiment against the war. The rest is history.

Fast forward to the War on Terror. While many Americans have doubts about our course in Iraq, the intensity of the anti-war movement's opposition does not come close to matching that displayed during Vietnam. Some of that has to do with the fact that large numbers of the American people still support the war. But part of the lack of intensity stems from the fact that most people have no real skin in the game. No one in America today is at risk for conscription into the military service. No one can be compelled to serve against their will. The War on Terror is being fought by volunteers. Therefore, many look at it as someone else's war—the most cynical call it "Bush's war." And many harbor an unhealthy attitude that since our soldiers volunteered to serve in the armed forces, they and their loved ones are estopped to complain about whether the war is warranted and how it is being waged. The thinking seems to be that members of the military assumed the risks in exchange for financial gain. Our volunteer soldiers are increasingly being viewed as "mercenaries" rather than "patriots." When questions arise about the hardships they and their families are experiencing because of long and frequent deployments, cynics increasingly invoke "caveat emptor" rather than expressing appreciation for the sacrifices that are associated with "duty, honor and country."

There is much to be said for an all volunteer force. Many who served with draftees in Vietnam and with all volunteers in other theatres indicate that they much prefer service with the latter. Volunteers, they maintain, are more highly motivated and have a greater sense of esprit de corps than draftees. Still, the danger of an all volunteer force is that the public will feel that it has less of a stake in the fortunes of America's fighting forces and the manner of their deployment. There is less likelihood, under such circumstances, that the public will mobilize in opposition to conflicts involving doubtful national security interests or that they will howl in protest if a war—even a just war—is prosecuted poorly. There is also an increased likelihood that America's military might will be deployed in pursuit of less than noble goals and on behalf of interests other than the common good.

If that happens, it will be bad for America and for the world.