THE FACT THAT Gov.-elect John H. Dalton chose to spend a day in Northern Virginia last week is encouraging. Perhaps he is willing to provide some of the leadership that is needed to let Northern Virginia become a part of the Old Dominion in fact as well as in name. If so, it will be a refreshing change from the past four years during which the Godwin administration made it clear they they (Northern Virginians) were quite different from us ("real" Virginians).

This estrangement between the Washington suburbs and the rest of Virginia has long been a serious matter. It occurs because many Northern Virginians are not natives and have a different view of politics and government from that held by, for example, residents of Richmond. It is reflected in the refusal, year after year, of many state officials to recognize that the needs of residents in this part of the state are different from the needs of those who live elsewhere. That refusal is often accompanied by an unwillingness to entertain the possibility that the proper role of government in a large metropolitan area is different from that role in Southside.

So it may be useful that Mr. Dalton and the surging Republican Party have some political debts in Northern Virginia. The area supported him in the November election, and it provided more than half of the winning margin of his running mate, Attorney General - elect Marshall Coleman. Both campaigned hard and often in the area, and both have been widely exposed to its people and problems.

The purpose of Mr. Dalton's recent visit was to listen to local officials, many of them Democrats, talk about those problems, especially those of transportation. We are glad Mr. Dalton listened. And we truly hope he heard. In fact, he may be obliged to change some of his basic premises in order to do right by his constituents. Local governments in the Washington area, as well as in the rest of Virginia, are hard-pressed for funds. Yet Mr. Dalton has shown little sympathy so far with efforts to provide them with more state money or to give them additional taxing power to raise the money on their own.

Mr. Dalton's reaction to proposals for a regional tax - on sales, incomes or gasoline - with the proceeds earmarked for mass transit is illustrative. His response has been that he wants "uniformity" in taxation throughout the state. That may seem an appealing idea, but it is neither logical nor sound. The major revenue source for local governments is the real-estate tax, which is anything but uniform; to attempt to make it uniform would be political suicide. As it is, each community sets its own tax rate on the basis of the cost of providing its citizens with the services they want. That is sound policy since it lets Northern Virginia have some of the things its citizens want - first-rate schools, libraries and parks, for example - that other communities don't care so much about. The same policy ought to apply to other taxes as well, so that each community can determine its own fate instead of having to rely on Richmond to decide for it.

It has always seemed strange that Virginia's governors, who traditionally are vigorous advocates of states' rights, shy away from supporting local rights, especially in Northern Virginai. Maybe Mr. Dalton will hear enough about the needs of this area to break out of that pattern.