Originally Posted by michaelchertoff
There are many examples of exactly this when people have lost their ID, such as leaving it at home or having it stolen. You can find examples in a search of this board.
If you see a distinction between this and refusing to produce ID, you're welcome to wait for a response on that point.
This past October, I left my house in the Midwest at 4:45 a.m. to make a flight to Arizona for a deposition at 12:00 noon PST. When I arrived at the airport parking lot I realized that I left my wallet with driver's license and credit cards at home. I checked in at the ticket counter, which was no problem because I had earlier booked the flight and have status with American. The boarding pass had the SSSS marking on the corners, but that secondary was no more intensive than the many others TSA has performed over the past 40 or so months. For this trip I had only my briefcase, because I made the round trip all in one long day. In short, it is possible to fly without an ID.