A curious question with little contextual information. You’ve been there, thus you know the circumstances. You’ve admitted you’ll be put up well, but have avoided responding regarding your assignment, role or organization. Photography in these locations is a moving algorithm of access, proximity, exposure and risk. Tell us, if you can, what control you may or may not have over many of these factors.
If you’re official, you’ll be in armored hard cars, the major drawback of which is that most have sealed windows. You’ll see the best photo prospects through glass passing through areas you are not allowed to hang about. I might think the real decisions have to do with lens reach, as only you know just how close you’ll be allowed to get/be with your subjects or how much time you'll have to just hang.
Tell us a bit more of how you will actually spend those 6 months.
I’m across the border, based in Peshawar, building roads and border security outposts in the FATA tribal areas along the Afghan border. General circumstances are not dissimilar. I carry a mix of M’s (M6 & M7), 2 CLEs and a IIIa, although never all at once.
Given large international presence in Kabul, film may be available. OTOH, only low-end commercial crap is available on my side of the border. Best to arrange your own supply, keeping in mind suggestions to get it shipped in. Beware that official pouch shipments are both x-rayed and heat zapped (to neutralize anthrax, etc), so are bad choices for film.
The suggestion of heavy-duty ziplocks is generally useful. Equally important is to stay alert to fast temperature changes for your equipment moving in and out of A/C (or heated, as winter comes on) cars. The fogging sucks dust into lenses and bodies, especially into areas you cannot reach with either brush or blasters. Watch where you put your equipment while traveling (inside the cars) to minimize direct blasts from a/c or heater.
Given what you already know about both situation and your role in it, take the gear that will serve you best. Then, come back and tell us all about it. Good luck.
Owen