THE BRITISH seem to have taken even themselves by suprise. The outpouring of affection for their queen, and the general spirit of celebration of her reign, went well beyond the expectations of a good many loyal Englishman. To the rest of the world, it was a useful demonstration of the other side to that country - the side that usually gets overlooked in the rush of events.

Events in the past few years have mainly drawn attention to Britain's well-advertised troubles. There is the unending guerillas warfare in Northern Ireland and the rise of separatism in Scotland. There is the increase of violent crime and the emergence of racial antagonism. There is the poor economic performance, the inflation, the precipitous slide of the pound. As you read about these things from a distance , it's easy to get a sense that the country is coming unraveled. But it's not. That was the message of the tremendous turnouts for the Jubilee processions in London and the spontaneous celebrations in hundreds of neighborhoods.

It's necessary not ot get sentimental. The troubles are real. But there's an analogy to the recent experience of the United States, which, after a decade of bitterly divisive war, political scandal and race riots, astonished itself last year with an amiable and most enjoyable birthday party. The popilarity of these civic celebrations is a corrective to the dire states of mind into which democracies sometimes talk themselves. American tend to judge Britain's condition by comparing it with the phenormenal prosperity of France and West Germany. But, as our London correspondent, Bernard Nossiter, has been arguing for some time, most Britons judge it in comparison with their own recollections of the 1930s and 1940s. Since then, for most of the population, everything has been constant - if slow - improvement.

Perphaps there's also another reason for the surge of spirit last week in London. Whatever costs the catastrophes of the 1930s and 1940s inflicted on Britain, the nation emerged intact in every respect. That's why, today, the relationship between Britain's subject and their country contains little of the ambiguity and doubt that persist in the major continental countries. In 1952, when Queen Elizabeth's reign began, Britain was the most powerful nation in Western Europe. Now, by most measures, it ranks third, behind West Germany and France. But to most of Elizabeth's people that kind of rating system had very little meaning. Certainly that was one of the truths demonstrated by the Jubilee.