"When the bells ring and tell the world I'm taking your hand/Folks from all over will come and see the wedding we've planned." — The Intruders

There is something about a wedding. There is the finery and the formality, of course, the dress with the long train, the tux with the bowtie that pinches, the speaking your heart and making your promises as everyone you ever knew stands witness.

There is, as well, the sense of ritual, the timelessness of ceremony that traverses and unites generations. Sean and May (he is the son of friends) got married in a Davie, Fla., park a little over a year ago, wreathed in white and hope and looking all of 12 years old. And at some point, reality shimmered, he was me and she was Marilyn, and it was a small chapel in Hollywood, Calif., on a Saturday in June 30 years ago — 30 years ago! — and we were saying our vows, giddy, young and stupid with love.

On Friday, it will be William and Kate's turn.

Much of the world will be watching, drawn by the promise of finery, formality and ritual on a royal scale. But see, there is something else about a wedding, something that speaks to deeper yearnings. In some sense, a wedding is an act of faith.

Lord knows we could use a few of those just now.

For an increasing number of us, it is conventional wisdom that we are in a time of decline, erosion eating at us like tooth decay. There is a sense that we have burned down our tomorrows and left ourselves only yesterdays to look forward to. There is a fear that we must henceforth make peace with lowered skies and diminished expectations.

This is quantified in a 2010 Gallup poll that finds 34 percent of all Americans pessimistic about the nation's future, more than at any time in the last 30 years. It is also quantified by marriage itself, which is becoming a rarity.

Small wonder. To get married is to make a bet on always and forever. To stay married is a function of will and work, even more than of love. The capacity and willingness to make that bet, to put in that work, to bear down with that will, are slowly disappearing from American life. Fifty years ago, close to 70 percent of all American adults were married. Now it's about 54 percent. Britain has seen similar trends. We marry less, we marry later, we make marriage a reality show, we see our cynicism validated by Hollywood marriages that pop like soap bubbles.

A wedding, then, is not just an act of faith but also one of defiance.

Particularly for someone like William who is, after all, the child of a marriage that began as a fairytale and ended as a horror story. Royal obligations aside, one could hardly blame him if he chose to bag the whole idea.

Instead, he will stand in the storied old church, promise himself to someone else and hear the same from her, like a million couples a million times before. There is something in it to gladden the cynical eye and hearten the pessimistic heart. So consider this a toast to the happy couple — and to acts of defiance and faith. Fifty years from now, may it be said that they achieved something that has eluded so many of us for so long we find it hard to believe in it anymore. May it be said they left that place as husband and wife.

And they lived happily ever after.

Leonard Pitts' column appears regularly. His email is lpitts@miamiherald.com.