The budget on which the House of Representatives is to vote this week reduces the 1986 federal deficit by $56.2 billion without raising taxes and without cutting Social Security or further reducing programs for the needy.

Since President Reagan proposed budget reductions of $51 billion and pledged in his campaign not to raise taxes, not to cut Social Security, and not to further shred the "safety net," one might have assumed he would welcome this budget rather than attempt to defeat it.

Instead, its approval last Thursday by the House Budget Committee was greeted by an intemperate press conference by the Senate Republican leadership and a hysterical letter from OMB Director David Stockman. The Stockman letter, full of phrasesuch as "cynical concoction" and "unconditional surrender," sounded like something written by the Ministry of Truth in George Orwell's "1984" rather than by an executive office once exceptionally temperate, responsible and professional. Why all the hostility?

The administration's defensiveness on the budget becomes clear if you stand back a bit and look at the fundamental issues rather than the fine print. The single major difference is simple: the Republican budget cuts Social Security recipients by $6 billion and the House committee budget does not, whereas the House committee budget holds down Pentagon spending by $6 billion more than the White House and Senate Republicans would like.

This is a major policy difference, but reasonable people can reasonably debate policy. This policy difference, however, illustrates once again a chronic problem of the administration: it cannot reconcile its goals and its resources, and therefore it makes commitments it cannot keep. In 1981 the president said we could escalate defense spending, cut taxes sharply and still balance the budget. We got $200 billion deficits. In 1984 he said we could escalate defense spending, protect Social Security and still reduce the deficit. We got a proposal to cut Social Security.

The defense spending issue is vitally important and requires clear thinking and clear policy. What is this administration's policy? Last August the president said we needed $295 billion in 1986 defense spending -- $43 billion above our current projection for 1985. In February the president said our national security required that military spending increase by $32 billion. In April he said $24 billion would meet our needs, but less would be "irresponsible." In early May he agreed to $21 billion. Now he says the House committee's proposed increase of $15 billion would decimate defense.

This policy trend should bring the president to our level by the Fourth of July. If not, Ceinberger can repeat his "discovery" of an extra $4 billion of apparently unneeded money last week when it appeared that the Senate Armed Services Committee might authorize a real defense cut.

The hard fact is that we have poured so much money into defense in the last four years that we cannot control it effectively. These increases have put so much money in the pipeline that the military budget will continue to expand rapidly under any circumstances. Even with the responsible restraint imposed by the House committee budget, defense spending will increase by $52 billion over the next three years.

And there are other important policy differences between the Senate and House committee budgets that will capture fewer headlines than defense and Social Security. The administration and Senate Republicans seem unable to refrain from picking at the "safety net," so there are cuts in Medicaid food stamps and child nutrition, in addition to the half-million people pushed into poverty by the Social Security COLA freeze.

No one can deny that the United States is currently borrowing its way toward economic debacle. Most Americans agree that is essential to reduce the deficit.

So it is essential now that all Americans -- including the president -- join in a good-faith effort to solve the problem. Intemperate partisan attacks will lend nothing to the debate.