As politicians and military experts again weigh the possibility of a draft, some Americans are calling for an alternative to military service.
Rep. Paul N. McCloskey Jr. (R) of California said in an interview that he plans to reintroduce and more actively push in Congress this session his proposal for a national -service system. Under his plan, 18-year-olds could choose between military service and social work, a system he said would improve the quality of US Army and reserve manpower.
Congressman McCloskey, a former US marine, said that although White House support for such a system now seems unlikely, President Reagan's recent renewal of draft registration has spurred debate on conscription.
''It shows that he is no longer dedicated to a philosophical standpoint'' of opposing a peacetime draft, Congressman McCloskey said, although Mr. Reagan has said he would institute a draft only in an emergency.
McCloskey's plan would require young people to choose between military service for two years, military service for six months with additional reserve duty, or a year of government-sponsored social work, all tied to varying educational benefits. Those not choosing an option would be eligible for a draft if needed.
Milton Friedman, Nobel prize-winning economist and a philosophical architect of the current All-Volunteer Force, said in a telephone interview that he opposed the concept of a national service program even more than he does a draft.
He compared the bureaucratic and regimental effects of national service to those of Hitler youth groups in Germany in the 1930s, although he has written that universal military training might be justified to maintain reserves of trained and prepared citizenry.
Nonetheless, no mandatory system will solve current personnel problems in the armed forces, he said.
''The problem with the military is keeping technically competent people. . . . The right solution to that problem is horizontal recruiting.''
''Horizontal recruitment'' would mean that the armed forces would compete in the job market for skilled -technicians unlikely to see actual combat, instead developing its own specialists by bringing them up through the ranks starting with boot camp.
Maj. Gen. Howard Crowell, chief of the US Army Recruiting Command, spoke about Army manpower in his office at Fort Sheridan, an old Army base on Lake Michigan where soldiers now monitor statistics and plan personnel strategy.
''Being a soldier is a little bit different than having a job,'' he said, adding that common military training for all personnel is necessary for good morale.
The general pointed to the Army's Cohesion, Operational Readiness, and Training project as an effort to improve Army quality regardless of whether troops are recruited or drafted. The project aims at improving unit effectiveness by keeping groups of soldiers together during their term of service.
Expressing some support for tying federal educational benefits to service, General Crowell said that such incentives must not ignore noncommissioned officers who might be more interested in salary bonuses than student grants as incentives for reenlistment.
Friedman supports using higher salaries rather than educational benefits as incentives for both enlistment and reenlistment, an approach that some label mercenary.
In answer to that charge, the economist related a conversation that he said he had with Gen. William Westmoreland during hearings on establishing an All-Volunteer Force during the Nixon administration.
''He said he did not want to command an army of mercenaries. I said to him, 'General, would you rather command an army of slaves?' ''
''I don't like to have my patriotic draftees called slaves,'' the general replied, according to Friedman.
''General, I don't like to have my patriotic volunteers called mercenaries,'' the economist said.