I think you did capture the essence of the truce and what makes the U.S. so great, bar one sentence:
"Given the huge differences between, say, a born-again evangelical in Georgia and a pot-smoking post-boomer in Seattle, no single cultural strait-jacket can ever hold America together."
Change "pot-smoking post-boomer in Seattle" to "pot-smoking post-boomer in Atlanta" and you really capture the U.S. - born-again evangelicals living in the same friggin' city (Atlanta) and working with and shopping with pot-smoking post-boomers. Hell, I was just wished "A blessed day" on the elevator by a complete stranger.
It really is a wonder that America can be one nation with such incredible diversity within its borders. And that's why I get so angry when people try to define the nation with the narrow margins of their own beliefs, such as those who say it's a "Christian nation." And, while citizens of other nations seem to spend most of their time killing their fellow nationals, we have learned to get along, or at least we have up until the current era of the politics of destruction.
We really need to learn a lesson from Iraq and Darfur and Northern Ireland and avoid their fate.
Note: Wizbang Blue is now closed and our authors have moved on. Paul Hooson can now be found at Wizbang Pop!. Please come see him there!