This did not happen in City Centre Mall. This did not happen in a Graveyard, where they dug up a body. This happened in a war-zone.

If you saw this happen on the Corniche, it would be the most horrific thing you had ever seen. To these guys? Peeing on the body of a person they have been (rightly or wrongly) trained to believe as the enemy and the evil that attacks their country, and stripping their dignity (which is what happened when they first joined the armed forces, to break them) is 1/100th of the kind of evil things they have seen in a war-zone.

This does not justify it. It does not make it okay. It is just putting the act into its proper context, not 'downplaying' it.

Your scale of moral compass of things you would do to others is, oh I don't know, say you call someone a bad name, that is a '1'. '5' is you stealing. '10' is you spreading malicious damaging rumours about someone, or maybe something more severe.

For these guys, a '10' is PUTTING A BULLET INTO A PERSON'S BRAIN. And that is not a hypothetical 'would you?' for them, it is a routine.
When you have 'killing' as your '10' of evil that you will commit, how far down the scale do you think pi**ing on the enemy is to them?