The changes you see are not always the ones that really matter. True, the new buildings invade what is left of the urban sky and demand to be noticed. The jets are sleeker and the freeways are faster and the television programmes are more insistently mindless than ever. But even after only eighteen months away – separated, too, by President Kennedy's assassination and all that has happened since – you are aware after a while of a hidden stream of change, a shift of accent and attitude that is hard to define but is none the less decisive.

You could call it a mood of self-appraisal, a critical undertone that is a new note in the carefully orchestrated harmony of America's need to conform. Of course the harmony was always a celestial hope rather than a terrestrial reality. The very structure of the United States has meant a constant tension between ‘the truths we hold’ and the local understanding of their application. The Supreme Court gives its judgments, the federal agencies move in to implement them, but Alabama is not greatly affected – yet. Nevertheless the change is there; sometimes publicly plain in such events as the sit-in protests on the Berkeley campus of the University of California, more commonly reflected in less sensational ways.

In the evolving life of the Catholic Church in America the external changes are indeed evident enough. Improvised altars facing the people have sprung up everywhere: unlikely trestle-tables that carry on a silent war with the shrines of St Jude and the fitted carpets.