Where did big bands and swing music go? They didn't leave. . . but many Americans actually believe they disappeared along with ballrooms, jukeboxes, bobby sox and zoot suits decades ago.  Band leader Brooks Tegler, who has recreated the great music of World War II with his Army Air Corps Review Big Band, offers a good response.  "In order for something to come back, it needs to have gone away.  Big bands have wrongly been put in that category.  They never went away." And that's the essence of the chapters of my  book about America's big bands, ballrooms and dancing's past and present.  And there's a good look at the future through the eyes of a number of young bandleaders from the east to west coast who carry on in the tradition of Guy Lombardo, Glenn Miller, Harry James, Woody Herman, Duke Ellington and a host of other music legends in their own distinctive way. The struggle to survive in the music business hasn't been without losses and a need for life support.  It did when Miller, Benny Goodman, James and Ellington were in their heyday.  It's a financially precarious business regardless of your talent. Inevitably, music and dancing evolved and matured.  The reasons are numerous and linked to our heritage.  But like marching bands on the 4th of July, imagine a country club new year's eve without live dance music and a big band.  Think about the many community social events and high school and college proms let alone wedding receptions that still insist on having live bands to play the foxtrots and swing numbers people enjoy.  My research shows that while there were approximately 800 big bands on the road during the swing era of the 1940s, today there are nearly 1,300 big bands, according to a Google search and  a review of hundreds of territory bands.  Consequently, neither the bands nor the music vanished. . . they scattered throughout the American countryside.