First the very fact that you distinguished offensive and defensive military activity carries the strong implicature that you think it’s important to draw such a distinction. The message this sends to everyone in the offensive part of the military is that what they are doing isn’t honorable, moral and worthy of respect by society but something shameful that needs to be swept under the rug. Remember a huge part of the reason we (our other modern democratic state) can deploy the military as cheaply as it does is because of an implicit societal contract to reimburse soldiers with favorable social status/gratitude.

Also the last thing the military needs is these extra distinctions tripping it up while in the midst of a conflict. You don’t want a contractor who is best able to serve a given need unable to do so because of this kind of lack of flexibility. Besides, even during a war of choice like the Iraq war if the public felt that soldiers were dying because some “defensive” employees were refusing to help on the offensive products the backlash would quickly erase the distinction.

Most importantly though because the distinction doesn’t make sense. Hell, I don’t think the distinction between civilian (whose economic output helps drive the war effort for a modern nation state) and a civilian who got drafted into the military is a sensible one to make much less this distinction.

“Obama increases Department of Offense Budget 30%”

That’s why.

As far as the contractors are concerned, inasmuch as they’re technical folk, some projects are sexier than others, but these already have signalling advantages with coworkers.

Why don’t more parts of the military, and more military contractors, officially distinguish themselves as more emphasizing defense over offense?

The very fact that essentially all military contractors are called “Defense Contractors” (as opposed to “Offense Contractors” or “War Contractors”) seems to imply that a lot of people do try to make that distinction. It makes them seem more essential, and less dangerous, to have around.

Now obviously a large fraction of “Defense Contractors” aren’t really about defense at all, but that’s another topic entirely.

The problem you solve is fundamentally “see and shoot”. If you are on defense, you see someone coming at you and shoot. If you are on offense, you see if you can find someone to shoot.

Anything you build to see can help you shoot, and anything you build to shoot needs to see. There’s really no simple way to separate offense and defense for contractors..