The military registration debate is reaching the floors of Congress. On the House side, a proposal tacked onto the defense authorization bill would require the president to begin registration of 18-year-old males in January 1981. In the Senate, the Armed Services Committee proposes the registration of males 18 through 26 to begin no later than January 1980.

Thus far, the issue has been inappropriately linked to the question of whether or not the volunteer army is working. This has happened largely because the strongest advocates for peacetime registration and the sharpest critics of volunteer forces are one and the same. As a result, many oppose registration for fear that it is but a first step in a conspiracy to return to the draft. It is important that Congress move out of the line of this emotional cross fire and consider the issue on its merits.

Registration was terminated by President Ford in 1975, a decision taken largely in the interest of economy but no doubt influenced by the view that a conventional war would not last long enough for mobilization to matter and, even if it did, reservists could fill the breach until the Selective Service System could be reconstituted and begin to deliver fresh recruits.

But a recent reassessment of the demands of an intense conventional conflict coupled with problems in manning the reserve forces have raised fears that the U.S. Army would run short of combat troops should the forces of NATO and the Warsaw Pact square off in a reply of World War II. As matters stand, the nation's Selective Service machinery, which is now "deep standby," could not deliver the first inductees to Army boot camps until some 110 days after a decision to mobilize. Allowing for training and travel, this would mean that the first replacements would not reach the battlefield until at least 200 days after mobilization, which many now consider to be too late to make a difference.

The Carter administration wants to speed up the process; as a first step, it has proposed increased funding for fiscal year 1979 and 1980 to improve the computer capabilities of Selective Service and to increase the size of its full-time staff from about 100 to 150. The administration contends that its modernized system would ultimately be able to deliver the first recruits within 30 days, in which case combat replacements would be available as early as 115 days after mobilization - considered by the Pentagon to be soon enough to fill out new units and replace combat casualties. Moreover - and this is important - the administration claims that this schedule would be met without preregistration.

But not everyone agrees. Critics question the feasibility of meeting such a tight schedule, even by a streamlined system. They discount the propsects for registering up to 6 million youths, storing the data on computers at regional sites, notifying inductees to report, giving physical examinations and beginning actual inductions - all within 30 days. Instead, they argue, peacetime registration would give Selective Service a leg up, virtually ensuring that the 30-day timetable could be met, with some proponents claiming that inductions could start within 12 days.

To resolve the issue, Congress should address two questions: To what extent is an enhanced mobilization capability necessary to the nation's security? Is peacetime registration necessary to achieve it?

To answer the first, Congress will have to sort out conflicting testimony of expert witnesses who have expressed widely divergent views of the number of troops that would have to be mustered in an emergency, how soon they would be needed and how best to raise them. Much depends on the validity of assumptions regarding the amount of warning time before hostilities commence, the duration and intensity of conflict, casualty rates and other factors over which there is wide disagreement. Whether the military could train, equip and deploy large numbers of recruits even if they were available is also open to question.

Should analysis lead to the conclusion that an accelerated induction schedule is a good idea, it is still far from clear that peacetime registration is necessary to accomplish it. Claims that the administration's proposed improvements will be enough to revive the Selective Service System should invite a healthy measure of skepticism, but so too should the claims that a failure to endorse peacetime registration would pose an undue risk to U.S. national security.

This is all to say that too many questions are unanswered and, until they are fully resolved, reinstituting peacetime registration - an act that would be sure to reopen old wounds - would be premature. Indeed, the debate should not proceed to a legislative conclusion on the basis of the incomplete, conflicting and often emotional arguments presented so far.

Rather, it would seem prudent for Congress to go along with proposals to beef up Selective Service, which needs to be done in any event, and give the administration some time to iron out the technical problems that are bothering the skeptics. In the meantime, Congress hould press the White House for a comprehensive, coordinated and coherent standby draft policy and legislative proposals to underpin it. This will also give all parties time to do their homework on other critical questions that have been left hanging: Should women register? What form should registration take? Face-to-face at draft boards? By postcard mail-in? Or passively, by tapping existing government files? How is compliance to be enforced and what penalties will be imposed for failure to comply?

Once answers are in hand, Congress will be in a better position to make the rational and careful analysis that an issue with such important social and national-security implications deserves. CAPTION: Picture, no caption