He has one, and he says it would be a better world if everyone did. He argues his case in his new book, The American Porch: An Informal History of an Informal Place (The Lyons Press, $24.95). (Related story: Cities that are made in porch heaven)

"It's one of those topics you think about in passing, but you know there's something more interesting there," he says. "It's taking the obvious and trying to do a good job explaining it."

Dolan, 52, a freelance journalist and documentary maker for National Geographic Explorer and the Discovery Channel, began his porch project after renovating his own on his bungalow in the Palisades neighborhood of the District of Columbia. About $10,000 later, he not only had a sittable porch, he had more than a germ of an idea for a book.

Where does the porch originally come from? Greece? Africa? India? The Caribbean? Dolan explores all theories.

And why did the porch, once the mainstay of American life, fall out of favor? Dolan explains that, too, although he isn't convinced it was the arrival of TV and air conditioning that emptied the porches on Main Street USA.

"They had been fashionable for some time, so I think people were just ready for a change."

Dolan also points out that the backyards of America were changing at the time following World War I, which made it more attractive to be out back rather than out front. Hint: Stables and outhouses were disappearing from the landscape.

"Houses without a porch probably had indoor plumbing," Dolan says, adding that it was almost a status symbol not to have a porch.

But not before most every politician, from presidents Garfield and Harding on down, used them for their own benefit — the porch being the perfect backdrop for the all-American message of family and home.

Although he acknowledges he's not sure he answers the question, Dolan says, he started out wanting to know why it feels so good to sit on a porch.

"I think it has to do with human wiring" is as close as he gets to the answer.

But every porch does not work. There are rules, he says, that need to be followed to have a porch work its magic. It can't be too high off the ground, for instance, or set too far back from the street. "There has to be the human interaction."

Screens? He doesn't really like them. He says they separate people. (Don't even get him going on decks.)

The porch is the middle ground, Dolan says. Not inside. Not outside. Neutral territory. There are certain degrees of intimacy, he says. "The porch is a welcome zone but not as intimate as, say, the kitchen." He likes to call it the "let's see" place, as in "Let's see if we like these people enough to invite them inside."

As for the resurgence in porch popularity, Dolan agrees there has been a return to the porch, mostly because of urban preservationists and new towns being built by neo-traditional architects and planners, places like Seaside, Fla., and Disney's Celebration, outside Orlando.

"Porches appeal to people as a concept," he says. "I think they're back to stay now."

He concedes, though, that many of these porches aren't used and are purely decorative, and that some are even too narrow to rock a good rocker on.

But one of the problems always facing porches has been money — too much of it. The more money you have, the less you use your porch. "The more affluent we become, the more we tend to insulate ourselves."

Dolan says he still sighs when he drives by a great porch sitting empty.