Really great Navy Luger Postcard on Ebay

[sheepherder]

There's been similar cards posted here, most seem to be from the Torpedo Division...

Was the 'Torpedo Division' a school???

I'm guessing that the pics are some kind of graduation picture, like from a school or training class of some kind...

But I'm curious as to what the Torpedo Division would have to do with sidearms??? Were torpedomen considered auxillary 'infantrymen' when an armed escort or boarding party [VBSS?] was required???

I can imagine that on a sub, everyone would wear many 'hats', and duties would be doubled or tripled...But why specifically a torpedoman???

And why not a rifle???