GERMANY'S center-right coalition has now won another decisive victory, for the very good reason that it read the country's mood more accurately than anyone else. This was a single-issue election, and the issue was German unity. In a curious reversal of roles, it was the opposition Socialists who kept querulously asking how much it was going to cost and whether it wouldn't require a tax increase. Chancellor Helmut Kohl and his coalition understood that western Germans, prosperous and secure, felt a compelling obligation to reach out immediately to those other Germans who had lived under foreign domination for 45 years and to worry about the costs later.

Chancellor Kohl is widely held to be an utterly provincial politician with little vision or imagination. Perhaps that's the secret of his success in negotiating national unity without frightening the Soviets, his allies or his own people. His minimal interest in anything beyond his own borders is reassurance that Germany won't use its new strength to fool around with geopolitical adventures. That's why German voters trust Mr. Kohl.

But not entirely; they didn't give him anything like an absolute majority. Post-Hitler Germans don't much like absolute majorities. Mr. Kohl and his Christian Democrats will still require the support of the much smaller Free Democratic party, which came out of the election a good deal stronger than it went in. That's partly a reward for skillful diplomacy over the past year by the Free Democrats' Hans-Dietrich Genscher, the foreign minister. But it's also meant to be a check on Mr. Kohl.

These returns promise political stability as the country undergoes the great economic and social strains of fitting its two halves together. While the two Germanys have been joined in the legal sense, in every other respect there is a long and hard way to go to unification. It will be helpful that the party balance is roughly the same in the former East Germany as in the West. This election also saw a powerful pull toward the center, another healthy sign. On the left, the Greens did poorly. More important, the far-right Republicans sank out of sight altogether.

The new unified Germany, under a strong and experienced government, has large responsibilities to its neighbors. It will be more influential than ever as the 12 countries of the Common Market move toward closer union. But the government that Germany has now elected will probably be judged abroad, in the end, by its contributions to strengthening Eastern Europe's new democracies and preventing economic chaos there.