I’d like some different perspectives on this. This is not meant to question or negate the heroics of the fallen, but I find it interesting.
We were fed the story of Snake Island. 13 heroic Ukrainian service members stood up to Russia until their dying breath. Not only is it a fake story but the number of soldiers is in the 80s.
Now, go back to the mess of the Afghanistan withdrawal where we lost 13 service members. They were glorified (and by all means rightly so) and revered around the nation and every bar in America.
I can’t help but notice the trend here. 13 heros.
I've found additional meaning.
13 is also the number of "great change" which follows from a situation like I've laid out above, where someone fails.
Failure is a means by which we can learn lessons and prevent future failure.
So 13 is also a "learning experience" but as it pertains to complete abandonment of the life you knew before.
This is why 13 is sometimes depicted by butterflies, as they evolve from a caterpillar and abandon the life they knew before for an entirely new life, unable to return to how things were before.
In that sense, you can see how a disaster is a form of this evolution.
Also, it makes sense.
13 looks like a butterfly wing.