THE WONDER of this administration is that the biggest deficit spender in history can continue deploring deficit spending. The president did it again in his speech Monday night. It's a good debating tactic, but bad history.

The president used to blame Congress for the deficit. There was no mention in those days of the administration's own role in pushing a defense buildup and tax cuts simultaneously, the miscalculation that the tax cuts would pay for themselves by unlocking the supply side of the economy, the further miscalculation that, particularly absent Social Security, even the Office of Management and Budget could think up enough domestic spending cuts to make the math come out even. If only Congress weren't so weak and porky, had some discipline . . .

Monday night's argument, on the contrary, holds that until this year the United States was in the midst of a success story on the budget. In 1983, the president said the other night, "deficit spending was . . . 6.3 percent of . . . gross national product; today that figure stands at 3.9 percent -- nearly a 40 percent decline in just four years." No matter that the reason has much less to do with the deficit than with the GNP -- the economy was pulling out of the deep 1981-82 recession in those four years -- nor that the 3.9 percent is still an estimate. "All of this is good news," the president said. "Or at least it has been."

What's wrong is that now Congress has failed; the budget process has broken down. The president sent up a "responsible" budget in January, "but instead of acting on it," he said, "Congress ignored that." Well, not quite. Actually, both houses voted on it. It got 27 votes in the House, 18 in the Senate. "If our budget reduction efforts are not . . . credible, we will be sending signals all over the world that the American economy is in trouble again," the president warned. Exactly -- and what does he propose?

He wants a constitutional amendment to make it harder to unbalance the budget -- an amendment that his own budgets could not have withstood -- and a line-item veto so that he can better pick and choose among the programs Congress approves. He also wants a "budget consensus"; "we're ready to talk . . . at any time," he says. But not, it appears, about any subject -- "not if the objective is additional spending, more taxes and less defense."

The problem is not the budget process; it is the content. The deficit this fiscal year is likely to be $180 billion. That is double what it should be this late in a long recovery. Domestic spending programs can't bear the burden the president assigns them. To ease down the deficit -- carefully -- there also needs to be a tax increase and a pause in defense. If the administration won't do it, and Congress can't, we have stalemate for the next 18 months.