It's time to take a trip deep, deep into the tmatt folder of GetReligion guilt. You see, with the Iran explosion and a bunch of other major news, I don't think we made a single reference to coverage of the Southern Baptist Convention meetings in Louisville. As anyone knows who has ever covered one, SBC gatherings are big sprawling affairs, even though they are no longer the must-cover events that they were in the 1980s during the civil war for control of America's largest non-Catholic flock.

When you are there, the daily stories go marching by, from the election of the present to some resolution about this or that political issue. This year, the mainstream press stirred a bit about the Southern Baptists voting to celebrate the election of the nation's first African-American president, even while stressing the many, repeat many, issues that divide Southern Baptists and President Barack Obama.

As you cover those daily stories, it is often easy to lose sight of the big-picture issues that are looming in the background. Then, if you decide to write about one of these larger stories, it's hard to crunch it into the small amounts of space that reporters are working with these days.

So let's pause to celebrate one such effort, by veteran scribe Bob Smietana of the Tennessean in Nashville, home of the SBC headquarters that many call the "Baptist Vatican." I know, I know, that nickname makes no sense in terms of church polity, but relax.

In the middle of a feature about the convention, Smietana dove into a very complex subject -- which is why the Southern Baptists, after decades of growth, have finally suffered some slight membership declines. This, of course, stands in contrast to the demographic earthquake that has hit the "Seven Sisters" of liberal Protestantism. If you are interested in a longer, insider's take on this SBC issue, see these two essays -- here and here -- by Will Hall, the head of Baptist Press.

But here is the heart of Smietana's crisp mini-look at this huge subject:

Three major factors derailed the Southern Baptist system.

First, the birth rate among white Americans fell. That was a problem because most Southern Baptists are white and because they found most of their converts among their children. ...

Second, Americans moved from rural areas into cities and suburbs. That's a problem because almost half of Southern Baptist churches are in rural areas. And Baptists have, until recently, started few new urban churches. Hall disagrees with some critics who think the decline in membership and baptisms is a spiritual problem.

"The problem is not a lack of evangelistic fervor," he said. "It's location, location, location."

The third factor? New churches that don't act like Southern Baptist churches. Those churches have often exchanged their choirs for rock bands, met in nontraditional places, and have preachers who dress casually and give edgy sermons. And many new churches also have dropped Baptist from their names as denominational loyalty fell.

Now there is a lot going on in there and, yes, there's a lot more that could be said. The keys, however, are the hard facts about demographics and the reality of the post-denominational age. However, when I was reading up on the decline issue -- I plan to write on it myself, sooner or later -- one thing stuck out.

When it comes to racial diversity, Southern Baptists are actually seeing a tremendous amount of success. Mainline church leaders may struggle to grasp this, but the most ethnically diverse churches in America are found in these three bodies -- the Roman Catholic Church, the Assemblies of God and, yes, the Southern Baptist Convention.

The SBC has been opening many Hispanic and African-American congregations and seeing increases in its ethnically mixed congregations. The Tennessean article notes:

There are signs that the Southern Baptist Convention may be able to reverse its decline. From 1998 to 2007, the number of ethnic minorities in the faith doubled, to 8 percent.

In other words, they have had success -- but not enough. Southern Baptists are not keeping up with the rising tide of ethnic diversity in modern America, even though they are doing better than most other denominations. That's the largest of the larger realities, especially when combined with the issue of declining white birth rates.

This is a very big story. I hope the Tennessean lets Bob return to it and dig much, much deeper.