May we assume that the Pledge of Allegiance is not being said in this school? After all, it might be an occasion for some students to pledge earnestly and loudly, and this principal seems to consider that sort of thing inappropriate!
Thinking back to the sixties here, can anyone imagine a child suspended from school for honoring the flag, and finally being escorted back into school by federal marshals? Past a gauntlet of angry illegals? Is that where we're going? Are there now areas of the US where the American flag is now considered hate speech, and local officials can ban it?
According to the video, you are assuming incorrectly. The pledge is said everyday according to one student and here all flags were banned not just the US flag and it was done because the principal felt they were distraction to learning.