WASHINGTON tends to see political campaigns as national struggles. But in this heterogeneous country, election results, especially in the off-year, flow as well from local choices. "All politics," Tip O'Neill likes to say, "is local." While that may overstate the case, it's true that campaigns are one way in which the regions of the country educate each other about their differences.

In the Silicon Valley, in Texas' oil towns, in the Southeast (except for steel-producing Alabama), the recession is only starting to hurt, and it seems temporary. This may also be true of parts of the Snow Belt that in other years have had declining economies: New England, New York City, parts of Pennsylvania and here in the Washington area.

You get quite another picture in the industrial heartland, west of the Appalachians and centering on the Great Lakes. There aging industries seem to be in irreversible decline. No one expects the auto, steel or rubber industries ever again to employ as many workers as they did in the late '70s. Foreign competition, outdated plants, overpaid workers, unimaginative managements -- these are all blamed for the region's agony, though the coup de gr.ace was administered by the oil price shock of 1979. The reflex of the heartland voters is to support Democrats in recessions, and the Democrats hope to win more seats there than was predicted even a few weeks ago. But these voters seem uncertain that even the Democrats have an answer for their problems. So the old reflexes -- based on confidence in politicians' solutions -- may not necessarily be forthcoming.

The Pacific Northwest and the Great Plains states are also hard hit by the recession, but their problems seem more curable. People expect that sooner or later the lumber and paper industries and wheat, corn and soybean prices will come back. Voters there may swing to the Democrats in the hope that they can accelerate that recovery.

In a sense, we have become two nations: one that hopes good times will return, though it is not exactly sure how, and one that fears the good times it knew will never return, and has no confidence that anyone can produce something better. When we look at the election returns, we need almost to look at these two nations separately. The desperation one finds in the industrial heartland is not seen in most other regions. There our economic problems, while severe, still seem possible to ease, if not end.