FOR AN ADMINISTRATION not always skillful in these matters, the Carter White House has managed the publication of its 1980 budget very shrewdly. All of the unpleasant tidings have long since been declared, hinted or leaked. The president telegraphed the basic restrictive position in his October speech on inflation. The internal dispute over the increase for defense rapidly became external. It's also been in the air for weeks that there might be a bit of tinkering with some of the social-benefits formulas. When the budget finally appeared yesterday, it was something of an anticlimax. There was no lastminute sleight-of-hand, in the manner of Lyndon Johnson, in which everything was magically (if perhaps only temporarily) resolved. As far as we can tell, there are no rabbits in Mr. Carter's hat. The budget turns out to be exactly as advertised.

The president's cuts are not so large or, except in a symbolic sense, so important as you might think from the shrieks of protest. The largest increases, where they exist, are in the largest of the present programs. The new initiatives, to use that traditional term, are minuscule. There has not been anoter president in the past generation who has been so cautious, or who felt himself so constrained, in using the budget as an instrument to set new policy. Like last year's, this budget signals no turns. The reason is the deep and painful ambivalence within the Democratic Party, and perhaps within Mr. Carter's own mind, over the money issues. Most people would like larger benefits. But most people also think that the deficit has to be worked down.

The quarrel over the increase for defense is already well advanced. But the more interesting quarrel, we suspect, will be the one over Social Security. The amounts of pension money actually under challenge in this budget are microscopic, but they are denounced by people who see them -- not altogether inaccurately -- as an attack on the principle that a benefit, once offered, must never be withdrawn or trimmed. With a steady rise in the proportion of the population over 65, even small changes now can have accelerating effects in coming years.

For defense, the president has asked an increase of about 3 percent over the expected inflation rate. It is worth noting that the increase for Social Security next year will be 5.5 percent over the inflation rate. The president's request for defense is $114 billion, not counting the military pensions. The budget for Social Security is $115 billion. The outlay next year for all federal pensions -- Social Security, militry personnel, retired federal workers and so on -- is estimated at $159 billion. The federal pensions are not only a much larger share of the budget than defense, but they are also rising much faster -- not least because most federal pension benefits are automatically linked to the inflation rate.

Just about half of the federal budget now constitutes direct benefits to individual citizens. Some of it is payment for health services, such as Medicare. Some of it is food stamps. Most of it is cash -- the monthly checks for pensions, unemployment compensation, welfare. Budget control will increasingly have to mean the review and, sometimes, the reduction of those benefits.

Mr. Carter's budget is, after all, only a first draft. Now it goes to a Congress that, over the past five years, has enormously expanded its capacity to impose coherent fiscal purposes of its own. The final version will be the budget resolution that Congress adopts next September.

Last January, Mr. Carter's original proposal for fiscal 1979 -- the present year -- called for a deficit of $61 billion. Congress reduced that deficit to $39 billion. Now, for the 1980 fiscal year beginning next October, Mr. Carter offers a $29-billion deficit. If the economy should go into a recession, that figure will rise automatically -- and ought to be permitted to do so. But if the eonomy's growth rate does not decline significantly over the coming six months, a deficit of even $30 billion will be too high. Certainly no one in Congress is likely to forget that they are now working on the budget for the campaign year that ends just a few weeks before Election Day in 1980.