Dutch Newchurch

Thank you Ernie.
Yes, the smoke was enhanced!
The inspiration came from seeing photos from Iraq and Afghanistan; I felt the bright sunlight in my original lacked drama.
I have a wooden garden fence. One winter morning there was bright sunshine after a hard frost, and steam was rising from the fence, back-lit by the sun light. I shot many snaps of that, with the specific intention of using them to add smoke to other photos. (I also do a fair bit of music photography, and sometimes enhance the stage smoke).
For this shot I simply copied the shot of the rising mist, and put it on top of the shot of the soldiers, as a new layer. I think I used 'levels' to add contrast and darken the added smoke layer, then masked it with a soft brush, to allow the three comrades to show through.
Happy to explain that in more detail if you wish.
There was some smoke, and dust, in the original, but not enough.
I kept the yellow marker on the rifle, to show it was a photo from a public demonstration,