On the level of morality, the more salient point is that there is no reason for this burning of books other than a pure demonstration of unjustified antagonism towards a group of people.
The argument that soldiers might get hurt over this, is more of a rhetorical weapon you use to assault the anti-muslim wing of the religious right.
On the practical side of US foreign interests, it doesn't help American interests in the Middle East to be perceived as being there because it is hostile towards Islam.
XI Wiki


