Its sponsors and the president keep chipping at the deficit-reduction amendment on the Senate floor to take important shares of the pain out of it. The more they rework it, the more it comes to resemble either 1) a showy effort on the part of those who brought us the deficit to demonstrate now how much they deplore it, and/or 2) a selective effort not so much to reduce the deficit as to use it as a lever to attain assorted lesser policy objectives.

The difficulty for the last five years has been that the deficit has been a residual element in policy- making. The president and the parties in Congress have had various programmatic or distributional goals -- cut taxes, increase defense spending, show themselves to be the stoutest possible protectors of the seventh of the population that receives Social Security benefits. The choice, particularly as framed by the president, has come down to letting the deficit rise or cutting an enormous swath through all other domestic programs. Not even the president has been able or willing to propose the requisite cuts, and the deficit has risen.

The amendment in the Senate was meant to re- energize this stale debate by requiring that deficit- reduction come first and by confronting the president and Congress with a much more difficult set of choices. In its original form it set deficit targets declining to zero over the next five years and decreed that if Congress failed to hit a target, the president would have to make spending cuts, in defense and Social Security as well as the domestic remainder of the government. It made no mention of tax increases, but the idea was that, rather than cut defense and Social Security, the president would likely agree to one. There was a hammer at everyone's head.

But the terms keep changing. To pick up support on the floor, the sponsors agreed that none of the burden would fall on Social Security; it would be exempt. Partly to ease the pressure on defense and partly to avoid deep spending cuts just before next year's elections, they have also stretched out the deficit-reduction schedule; the amendment now would probably have no effect for a year. Meanwhile, the president, in professing "enthusiastic support" for "what might well become historic legislation," has served oblique notice that he would not expect it to affect defense. In "a personal caveat" in his radio speech on Saturday he reminded listeners that Congress has already agreed (in this year's budget resolution) to defense spending increases of 3 percent per year after inflation over the next several years. "And next year I will propose those amounts already accepted as necessary for keeping the peace," he said.

The sponsors say that defense remains subject to the terms of the amendment, but that is clearly not the way the president understands or intends it. The stakes are too high not to have agreement on the rules. The amendment would have some seriously uneven effects within the Defense Department. The theory is that, to avoid these, the president would agree to a more rational budget. But to the extent that defense became exempt along with Social Security, there would be no pressure on him to agree to anything. The amendment would then only seriously affect the domestic programs that have been in the balance against the deficit all along. It would be a stronger license to dismantle them. It sounded a week ago like a good idea. It begins to sound increasingly like a bad one.