I feel obliged to respond since I see some fallacious argument being peddled here like PA has less PTSD than US Army ? And why is that ?
Our soldiers are not stretched by any means and with the emergence of drones, are not exposed much to explosions and similar situations on a daily basis. Which is in total contrast to PA.
In fact PA now functions as a police in some cities with high no of such incidents. PA simply doesn't have enough resources to follow up and research the matter can be the probable reason for such PTSD cases going unreported !
While you are not incorrect, there is another side to the argument. The relative lack of security in countries like Pakistan from the earliest of days where a soldier or officer sees it exposes that person to a level of "immunity" to certain day to day incidents. Take my own example, I was born and raised in a city where I have been mugged multiple times at gunpoint.. have had bullets rain down on my house, been at least 5 times within 5km(and in one case 400m) of a major bomb explosion and seen the severed head of children lying in the street from something as silly as a kite string coated with glass. Life here is cheap unlike western nations so that value of life and the shock of it going takes a little longer to settle in. These incidents, little by little have that rather deplorable effect of inhumanity upon one's psyche. So whereas in my city I am used to gunfire at random, if I go to a relatively safer city like the Capital and hear gunshots.. I will not panic and move very orderly to a safer position I am used to.
It does not mean that I too not have some form of PTSD.. mine is from motorcycle riders since that is the vehicle of choice for muggers.. so even in a relatively safe environment(as @jhungary mentioned).. I treat all motorcycles with suspicion and instinctively block their path towards my car doors.
Another example can be taken of the SF team that went in to clear out the school of terrorists in the Peshawar Attack. Throughout their operation the men were stoic and surgical, but the minute after the team gave the all clear..they all collapsed on the floor and sobbed away uncontrollably.
So the fact is that PTSD does exist, but the Trauma build up is not sudden as might be more common with ISAF forces.. but quietly building up over time. That does not go to say that PTSD is less or more.. but rather the way PTSD builds up is different and its effects or how it shows may also be quite different... perhaps a new term should be coined for the PA(and many Pakistanis) which is CTSD( Constant Traumatic Stress Disorder).