Melvin R. Laird was secretary of defense from 1969 to 1973 and counselor to the president for domestic affairs in 1973 and 1974. He represented Wisconsin in the U.S. House from 1953 to 1969.

Just over 40 years since the United States implemented the all-volunteer military force, some are once again suggesting that a draft force could be better. I managed development of the all-volunteer concept that President Richard Nixon endorsed, and I believe that returning to the draft would be a mistake. No president has advocated a return to conscription, Congress does not support it, and the American people would not stand for it — all with good reason.

The all-volunteer force has surpassed expectations. After more than a decade of sustaining combat operations in Iraq and Afghanistan while meeting other global obligations, our force has been successful by virtually every measure. The “total-force” concept, which I conceived, more closely links active-duty, National Guard and reserve military components. The volunteer military is more intelligent, fit, committed and representative than ever. Moreover, it has proved more cost-effective than a draft force.

Each year about 160,000 young men and women volunteer for active duty. An additional 110,000 volunteer for the reserves and the National Guard. Twenty-five thousand others are commissioned as officers, according to Defense Department data. Last year marked the 27th consecutive year in which the Pentagon has exceeded its quality standards for active-duty recruits. Half of all recruits are in the top two of the Armed Forces Qualification Test’s five categories, Defense Department personnel data show, with only 1 percent in the lowest. In the last year of the draft, only one-third of recruits were in the top two categories, with 25 percent in the lowest. Whereas only three-quarters of youths nationwide graduate from high school, all military recruits are required to have graduated. (During the last year of the draft, only half of recruits were high school graduates.)

Young people join the military for a variety of reasons: skill training, education benefits, ad­ven­ture. But the primary reason people volunteer and continue to serve is service to our country. They seek to be part of a respected organization larger than themselves. The all-volunteer service is that organization.

Some contend the draft is needed so that military sacrifice and risk may be more equitably shared. Ironically, a fundamental issue the Gates Commission on an All-Volunteer Force cited when the draft was discontinued was that it was inherently unfair. Among the issues the commission also cited was policymakers’ inability to adequately answer the question: Who shall serve when not all serve? Nobel economic laureate Milton Friedman, a member of the commission, summed it up by saying that conscription was inconsistent with the American values of choice, personal liberty and a free society.

Unfortunately, the majority of those who would be eligible for the draft today do not meet the standards for military service, for physical fitness and other reasons. People are the military’s most important asset. But if the objective is to maintain at reasonable costs an effective military force, the draft fails this test. If the objective is to require all young people to serve their country, there are numerous possible alternatives beyond making the military the only outlet.

Some critics argue that our voluntary military does not represent the society it protects. The facts refute these contentions: Recruits come from all parts of the country, from all income levels. They are all races and ethnicities. The force mirrors our diverse society, with black and Hispanic recruits reflecting their share of the population — about 15 and 17 percent of youths, respectively — and an increasing number coming from middle- and upper-income households, Defense data show.

Some have argued for the draft as a cost-cutting measure. But this is misguided. For a given level of force effectiveness, a volunteer force is less costly than a draft force. Among the reasons: A conscripted force has a higher level of turnover. Draftees tend to serve shorter terms and reenlist at lower rates. Training costs are therefore higher, and increased training time means less operational performance time. During the draft era, about one in eight stayed after his first term; with the volunteer force, closer to one in two wants to stay. A volunteer force is also more motivated. People perform better when their service is voluntary as opposed to coerced.

Although there is no good argument for returning to the draft, our volunteer force’s success has pointed up one reason for concern: The exceptional effectiveness and motivation may be an invitation to overuse and even abuse such resources. We may be near or in such territory now. There are limits to what can reasonably be asked of any defined set of volunteers, even when they are the best.

The all-volunteer force has served our nation well for more than 40 years — in war and peace, through social and demographic changes, floods, hurricanes and more. We owe the brave men and women of our military thanks — and a true assessment of the impact of national service.