THE HOUSE Budget Committee acted courageously in its marathon session last week, and came up with the first concrete evidence that balancing the federal budget may be politically possible. There is something for everyone to hate in the committee's list of cuts, but that was almost foreordained.It's one thing to be for restraints on spending, another to favor particular restraints. Since the congressional budget process was invented in 1974, the discipline required to do this has been hard to come by, and it is important to remember that the committee's action on Thursday night was only the first in a series of excruciating steps. But it was a vital one, especially when you consider that the House has been the customary barrier to budget discipline, as distinct from the Senate, which has generally had an easier time reaching consensus.

For once, the Republicans on the committee did not break with its chairman, there is a strong possibility of bipartisan support for the First Resolution when it comes to the House floor. But, unfortunately, in taking steps to hold the Republicans, Chairman Robert Giaimo lost the more liberal members of the committee on the final vote. It will take some delicate negotiation over the next 10 days to bring the committee into agreement, an effort well worth making. Liberals have often warned each other that if they don't participate in economizing, others less well disposed to their favorite program will make the cuts for them -- and with meat cleavers. The warnings have been right. So continued participation of the liberal Democrats in this process is essential.

The fate of this resolution on the House floor is not just a test of the members of the House. Over the next 10 days, congressmen will be hearing a great deal from organized special-interest associations. They need to hear a clear signal from the White House that restraint is expected and supported, even if it does not come packaged precisely as the administration might have wished. For this reason, the president's pledge on Friday to protect aid to distressed cities, through an entirely laudable objective, was probably badly timed. Congressmen also need to hear from their constituents that they as citizens are willing to give up a bit of their own special interest in order to achieve the larger goal.

The importance of such a demonstration of political will is enormous. Large segments of the electorate are convinced that the federal government lacks the political courage to control itself, the discipline to set a goal and then reach it. Balance itself may be less important than demonstrating the ability to work together to accomplish it. If the goal is not achieved, those who advocate the foolish idea of a constitutional amendment as the only means of reining in federal spending will be headed for victory. Many changes must still me made in the actual substance of what goes out of and what stays in the budget. What should not be open to negotiation is any possibility of letting the enterprise itself fail.