The Circus Disaster March

I am curios to know if anyone knows why "Stars & Stripes Forever" composed by John Philip Sousa became the "disaster march" for the circus?  Derek Rose,

Although there is no concrete evidence as to why that march was used the most likely reason is that everybody that has ever played in any band has played "Stars & Stripes Forever", and knows it backwards and forwards by heart without needing any music to play it.  Additionally, all the circus personnel are familiar with the march and have heard it numerous times before becoming employed by the circus.  This means when that particular march is played everyone involved with the circus will immediately recognize it and know that something has gone seriously wrong such as a fire, blowdown, fight, or other emergency condition that calls for all employees of the circus to appear and participate in remedial action.

Information provided by Fred Dahlinger, Jr. of the Circus World Museum 

and Bob Peckham of Windjammers Unlimited, Inc.