Just show them this picture of schoolchildren doing the "Bellamy salute" as they recite socialist Francis Bellamy's "Pledge of Allegiance" in school;
http://judgeforyourselfnow.wordpress.com/2010/10/05/bellamy-salute/
http://en.wikipedia.org/wiki/Bellamy_salute
http://en.wikipedia.org/wiki/Pledge_of_Allegiance
I'm afraid that if you were chosen to debate the motion and have to SUPPORT the Pledge then you basically got the end of the sick that they poked the dog-poop with, not the end they were holding!
Fundamentally, the Pledge is"unAmerican" on almost every level; it's a vow to defend an inanimate object!