The Pentagon budget debate is now in its nibbling, niggling, and nudging stage as lawmakers and administration officials juggle the substance and politics of defense spending.
The Senate has yet to set its overall budget goals for the coming year, but the Armed Services Committees in both House and Senate have begun the task of shaping military spending. As expected, Congress is not lopping off any big weapons, but is trimming around the edges of the administration's $280 billion 1984 defense plan.
It has started in those areas that the Defense Department says could impair readiness to fight. The House Armed Services Committee rejected a Pentagon request to increase uniformed military personnel by 37,300. Defense Secretary Caspar W. Weinberger says the additional troops are needed to maintain and operate new ships, planes, and other gear the military is buying with congressional approval.
Since Congress is likely to add money for the National Guard and reserves (popular items back home), the Pentagon chief says savings from freezing active-duty personnel ''are quite illusory.''
For defense spending, the largest item in the federal budget, the final outcome of what has become a nearly year-long legislative process is likely to turn on two important factors: how well the Pentagon is managing the huge sums provided it, and the perceived size of the Soviet threat.
President Reagan has said that ''in virtually every measure of military power , the Soviet Union enjoys a decided advantage.'' This year's edition of the Pentagon document ''Soviet Military Power'' is a better-balanced study than those in past years in that it includes more comparisons of NATO and Warsaw Pact force levels. But most administration spokesmen continue to insist that the United States remains in a catch-up position relative to the USSR.
Sen. Carl Levin (D) of Michigan, a member of the Senate Armed Services Committee, last week issued a rebuttal showing many military advantages enjoyed by the US and allies. His report, drawing on Defense Department and Defense Intelligence Agency data, is titled ''The Other Side of the Story.''
It shows that the US (either alone or in concert with its allies) is ahead in strategic nuclear warheads and bombs, heavy and medium bombers, strategic and tactical airlift aircraft, naval cruisers and destroyers, mine warfare ships, total ground forces in Europe, and total uniformed forces, among other things. It also cites the Pentagon's own figures showing that the US is ahead of the USSR in 15 of the 20 most important technology areas key to improving military capability.
The Pentagon says its belt has already been tightened and that program and management initiatives reflected in the '84 budget will save nearly $30 billion. This includes canceling and reducing some 120 marginally effective programs, multiyear procurement of some weapons to reduce unit costs, and eliminating some travel and consultant services.
Some of these initiatives are as simple as tightening up dining hall controls to curb food stealing, thereby saving $88 million.
Others are more complex, requiring a ''more is less'' logic to justify. For example, the Navy next year will buy 24 F-14 Tomcat fighters, instead of the six planned by the Carter administration for 1984. The Pentagon claims the move will result in a more economical production rate and save $132 million in per-unit costs. Likewise, the Navy says it will save $800 million by building two new nuclear aircraft carriers at once, even though the purchase of support ships and aircraft will push the total bill much higher than critics say should be spent.
''The bottom line is, the defense budget is bigger,'' concedes a Pentagon official. ''But that bottom line does not mean that some savings aren't there.''
The General Accounting Office, however, recently looked at the Pentagon's ''Economies and Efficiencies Program'' for the current fiscal year and concluded that 70 percent of the claimed savings were questionable or not supported by department actions. Savings from multiyear contracting and economic production rates were overstated, the GAO found, and most projected savings from reduced travel have not been realized.
''We disagree and will continue to disagree with GAO's interpretation of our budget methodology,'' the Pentagon stated in releasing its new economy and efficiency figures for the coming year. But such analysis will likely influence Congress as it molds '84 spending.