THE IDEA is being bandied about in congressional and business circles that the Treasury's tax reform plan ought to be put on the back burner for a while. Support for this idea comes in part from people who would lose some advantage to tax reform. But it is also supported by many people who favor reform but are concerned that it will distract attention from the need to reduce the deficit. The two objectives, however, are not really in conflict: Tax reform may be necessary before the public is willing to make the sacrifices needed to balance the budget.

The Treasury's tax reform -- the main features of which were warmly endorsed by the president on Friday -- is not designed to increase revenues. That has reduced interest in the plan among congressional leaders, such as Sen. Bob Dole, who are normally strong supporters of tax reform, but who see the need for fast action on the deficit. But Sen. Dole is living proof that a determined leader can make progress on both fronts simultaneously.

Back in 1982 Mr. Dole, then Finance Committee chairman, pushed a major tax bill through Congress while, at the same time, actively participating in spending-reduction measures. Like the Treasury reform plan, that tax bill ran counter to the interests of many tough lobbies. And Mr. Dole's task was in some ways even harder in 1982: That time he did not initially have strong White House backing, and the 1982 bill, unlike the new Treasury plan, raised taxes without the important consolation of much lower tax rates for most taxpayers.

Dual-track action on tax and budget reform is not only possible but essential. As columnist James Kilpatrick pointed out recently, Congress needs to act early next year to avoid being overwhelmed by election pressures in 1986. But a more important reason is that, in Mr. Kilpatrick's words, "the present tax code is indefensible." Numerous opinion polls, including a recent survey carried out for the government, show the great majority of people think that the tax system is so ridden with loopholes that it unfairly burdens the average working person and encourages cheating. A country believing that its government is financed by an unfair and corrupt system is likely to be reluctant to make the broad sacrifices needed to put its central finances back on a sound basis.

As the president pointed out, the Treasury's plan would make all the changes -- closing loopholes, eliminating preferences, lowering tax rates, relieving burdens on moderate-income families and requiring all corporations to pay a fair share of taxes -- needed to rebuild confidence in the tax system. It is, as the president says, "basically a fine proposal." Why wait to get started on it?