The choir director had actually asked a security guard if singing the anthem was OK and told yes, it was OK, making the actions of the superior security person even more shameful.
I uh, don't think that counts as a "permit".
Free speech doesn't require a permit. Only ticky-tack idiots would construe this as a performance. Any walking down the street whistling or even sauntering would then have to be considered a performance.
"Sauntering". I like it. Points for working in the word "sauntering". And even more points for working in the Malvina Reynolds reference.
But this is a choir, being conducted, in a regimented structure. That's a "performance".
Now if these authorities declared "you can't perform that particular song", you'd have a point.