This was to have been the Year of the Balanced Budget, the ultimate vindication of Congress' usually creaky, often snarled and always endangered budget control process.

Instead, Congress last week passed yet another red-ink budget, a hastily slapped together spending blueprint that was as hard to pin down as the leaves falling outside the Capitol.

"This," said Sen. Henry Bellmon (R-Okla.), a man of plain-spoken wisdom when it comes to budgets, "was not a banner year."

Yet for all the faults that its supporters readily concede, the process that produced the $632.4 billion spending ceiling and $27.4 billion deficit for fiscal 1981 was not a total failure.

In retrospect, with a recession in the offing, it was economic folly and political delusion to think that a deficit could be avoided. Measured against other achievements of the outgoing 96th Congress, the budget process might even be a modest success.

The budget process itself cannot force Congress to spend less. The only discipline in it lies in requiring Congress to acknowledge and put its name to whatever deficit its spending instincts and economic judgment combine to produce. But this requirement is important.

It forced Congress to focus as never before on its priorities and begin to tame its spending appetites, at least on the domestic side.

It required cuts in existing programs, although less than originally planned, to meet budget goals.

And it resulted in a budget ceiling, unrealistic as it may be, that will press the incoming Reagan administration and new Congress to deal swiftly with even bigger spending cuts.

Perhaps most important of all, it caused pain among the powerful and it survived. The cries of anguish from threatened constituencies may be eloquent testimony to its achievements and potential for the future.

Rep. Leon E. Panetta (D-Calif.), who ranks with Bellmon among the most thoughtful congressional budgeteers, believes it was a mixed record but one that proves a need for the process to continue in strengthened form.

Congress' failure to meet its earlier spending targets -- and to do so by the deadlines it prescribed for itself -- meant a "gradual erosion of the basic discipline of the process and more fuel for the arguments of those who would abandon it," said Panetta in summing up the record.

But Congress' use for the first time of the so-called "reconciliation" mechanism to force cutbacks in existing programs -- coupled with the discipline inherent in trying to balance the budget -- were significant gains, Panetta added.

It can be argued, in fact, that Congress played pretty well until the last few minutes of the game, when it simply fell back and punted.

It can also be argued that it did the right thing for the wrong reasons.

Hardly anyone on Capitol Hill believes that the "final" budget resolution that Congress adopted last week in a rush to end its lame-duck miseries by Dec. 5 will actually turn out to be final. Many lawmakers, Democrats as well as Republicans, believe another budget resolution is likely for fiscal 1981 next year.

According to House Budget Committee estimates, the budget assumes $18 billion in spending cuts that Bellmon, for one, thinks will be impossible to achieve despite reassuring sounds out of the Reagan camp.

"Any talk of $18 billion in cuts is just so much rhetoric," said Bellmon, who is retiring this year and hence has no stake in self-delusion.

For one thing, the fiscal year running from October 1980 to September 1981 will be about half over before the cuts can be made -- in effect doubling their impact on programs and services.

If that weren't bad enough, the supposed budget ceiling is $7.2 billion below appropriations bills already passed by the House and $2.5 billion below projected Senate spending, meaning that Congress was well on its way to busting its budget ceiling before it was even adopted.

Moreover, Bellmon says interest on the public debt is underestimated by $1.7 billion, entitlement programs by $2.5 billion, disaster relief by $1 billion and other costs by enough to add $11.2 billion more on top of the deficit. In a letter to President-elect Ronald Reagan, Bellmon warned of a likely $45-to-$50-billion total deficit, only slightly less than the $59 billion deficit for fiscal 1980.

The House-Senate budget compromise was patched together in such haste, with no relish for any more haggling over priorities, that the two houses simply agreed to disagree on many critical details, including basic economic assumptions and guidelines for spending cuts.

This has the effect of giving Reagan and the 97th Congress an unusual degree of latitude for formulating spending as well as tax plans from the start, taking seriously Reagan's announced plans for a spending cut of 2 percent or more as well as a tax cut.

Graciously put, it might be said that the old crowds didn't tie the hands of the new crowd. Cynics would say the Democrats gave the Republicans, who will take over the Senate as well as the White House next year, more than enough rope with which to hang themselves from their campaign platforms.

But the function-by-function spending totals envisioned in the balanced-budget resolution of last spring had an impact long before the final resolution was adopted -- producing, among other things, defense spending that increased more than twice as much as spending for domestic programs.

And, according to Senate Budget Committee Chairman Ernest Hollings (D-S.C.), overall spending actually declined by 1.4 percent in terms of real dollars, discounted for inflation. For most discretionary domestic programs, the real-dollar decrease was more than 15 percent, he told the Senate last week. One can argue whether this is wise public policy, but it suggests, as Hollings contends, that the process is more than an idle exercise.

Its future is -- as always -- in doubt.

Many liberals have been suspicious all along because, especially in Congress' recent pro-defense mood, the budget process is used mainly to cut social programs. But the liberals' numbers will be sharply reduced in the new Congress.

A more serious threat to the whole idea of congressional budget control may come from a House Republican push, which failed at least temporarily last week, to restore the presidential power to impound (refuse to spend) money that Congress has appropriated. This would shift the primary burden for spending control back to the White House, where it was before the Nixon-era impoundment wars that prompted passage of the 1974 Budget Control Act. A more likely prospect, according to some lawmakers, is a strengthening of the process under which the president and Congress can defer or rescind spending.

The 97th Congress will also have lost some of the Hill's leading budget pioneers, including Bellmon and House Budget Committee Chairman Robert N. Giaimo (D-Conn.), who also did not seek reelection. Edmund S. Muskie quit as chairman of the Senate Budget Committee last spring to become secretary of state. Both Muskie and Giaimo were forceful, often angry, voices for restraint among Democrats.

Still another problem is the potential for an escalation of House-Senate differences when the Democratic House and Republican Senate convene in January. However, liberal losses in the House in this month's elections point to an even stronger budget-cutting coalition than exists now.

Although he won't be around to see it, Bellmon, disappointed as he is in the budget results this year, believes the process is here to stay as a useful vehicle, "Its viability is great for the simple reason that Congress can't afford to go back to the old haphazard ways," he said.