BILL CLINTON'S accomplishments as president have been more political than substantive. Partly that reflects the fact that the Republicans controlled Congress for most of his two terms. The tax increase at the heart of his first budget helped to restore both the government's finances and the tax code's progressive edge. In the first budget of his second term he achieved a still under-appreciated 50 percent increase in federal aid to higher education in the guise of a tax cut that helps defray tuition.

The victories otherwise have been more tactical than structural. Much of his success has consisted in confounding the Republicans as they pursued their own agenda. In this, he has been much helped by their ineptitude. The legislative year just ended is the latest example.

It began with a great deal of talk about the major tax cut the Republicans were prepared to enact to keep the Democrats from spending the anticipated budget surplus. They dared the Democrats to resist. The president's entire budget was built around preventing the tax cut from occurring -- keeping the money in the public sector to help meet future public needs. "Save Social Security first" was his motto; he intermittently invoked Medicare as well. No matter that the president himself had no plan to save either. This was politics, not substance, and politically he was right; these are in fact the two great long-term costs that make it folly to grant a significant tax cut.

The Republicans passed their bill, which carried the added political baggage of being tilted hugely toward the well-to-do. He vetoed it, as promised. There was virtually no public reaction, and the issue now has faded, though it has hardly disappeared. The Republicans may try to pass a smaller tax cut in the run-up to the election, and cutting taxes remains a totem in the Republican presidential campaign. But on what was supposed to be the defining issue in 1999, the president won a major victory, partly because the merits were strongly on his side. The Republicans' latest position is that they want to save Social Security even more than the Democrats do; they would use the bulk of the surplus to pay down debt in its name. That's pretty much what the president proposed earlier in the year; the principal difference is that the Republicans have become more zealous about it.

The rest of the year was consumed in fairly minor maneuvering. The Republicans raised defense spending, but not before the president anticipated the shift and beat them to the head of the parade. The Republican leadership is blocking campaign finance reform, which allows the Democrats to champion the cause without having to fear the result. Long, loud battles have been fought about mostly modest bills to regulate managed care and handgun sales. If the gun bill were half as fierce as the rhetoric on either side, it might be worth having.

Big bills are out. The president sent up a health care bill that was too big in 1993, and suffered a humiliating defeat; the Democrats lost control of Congress in the next election. He sent up a major tobacco bill last year and lost again. He continues to have trouble mustering majorities for trade legislation. The welfare reform bill he proudly signed in 1996 was in our judgment a reverse accomplishment -- again a political act, the long-term effect of which will be to weaken a part of the safety net on which an eighth of U. S. children used to depend.

Welfare is one of a number of issues on which Mr. Clinton has shifted and blurred the position and image of his party to protect it from the traditional Republican attacks that it was an instrument of tax and spend, soft on welfare, weak on defense and crime, etc. The party is thought to benefit from the insulation. The question is, at what cost has it been bought?