There’s a myth in many cities that there was once some golden past, and that everything would all be all right if only this could be restored. The best answer to that was given by the late Ed Koch, when he was running for mayor of New York City in 1977.

When an elderly woman came up to him and said “please make it like it was,” Koch said, gently but truthfully, “it was never like it was.”   Metropolitan Detroiters, especially white ones, are, I think, very prone to false nostalgia.

Yes, the city was in many ways more prosperous sixty-five years ago, when the population probably touched two million, just before the Lodge Freeway opened up and the city started to empty out.  But there was overcrowding and pollution, clouds of cigarette smoke in every restaurant, and if you were black, it wasn’t all that great a time.

It was even worse if you tried to have an interracial marriage, and you might risk being killed, or at least beaten up, if you were openly gay.   Well, we’ve fought all those battles, more or less, and in recent years, we’ve had new waves of immigration, largely from Arabic countries. These days I’ve been hearing African-Americans express dismay that new groups were coming in, and fears that they will take the jobs they’ve been waiting for.

Whites, on the other hand, tend to grumble about an onslaught of new cultures they fear will dilute what it means to be American. Well, guess what. Both groups need to get over it.

Every study has found that immigrants are job creators, not job takers. This is a nation of immigrants, and always has been.  And every new wave of immigrants has faced discrimination. Help wanted ads in the 19th century often said “no Irish need apply.” In many parts of the country, the original Protestant settlers were horrified by the in-migration of Roman Catholics, who they regarded much as too many of us look at Muslims today.

And ironically, once each new group started to become accepted and assimilated, they tended to feel that the boat their ancestors arrived on should have been the last boat.

That’s what we are facing now.  I think there is a difference, in that many of today’s immigrants are prouder of their culture and traditions, and often want to keep them. A newspaper editor in Ohio whose parents came from Syria told me that he didn’t know a word of Arabic, or much of anything about his ancestral culture and traditions, because his parents wanted their kids to become fully American as quickly as possible, so they would be accepted.

There’s something sad about that.  It is true that a few contemporary Muslim immigrants have created communities here where they can live just the way they did in the old country.

But that too is unusual.  America at its best is a nation where everybody works together and celebrates common joys and sorrows, but where individual people and groups also honor and celebrate their cultural traditions. I drive to work every morning past a community of ultra-Orthodox Jews, some wearing fur hats, some large black hats, and I am happy they are here.

America is a constantly fluctuating ethnic kaleidoscope.

I think we should do all we can to enjoy it.