national anthem (like national flag) represent whole of a nation.. its people, land, its essance, soul, everything..... when we respect the anthem (standing up n so on....(like salute to national flag), we do respect the essance of a nation, its people et al.
Now if we "LEARN" to respect our elders, family. parents..., we MUST learn to respect our (and others too) national anthem, national flag.
..to add, anything "forced" is bad.