All photography is manipulated, in the nature of things, even 'real' B+W. We choose where to point the camera, when to release the shutter. Then we crop, dodge, burn... That's before you consider the possibility of staged pictures.
I have shot propaganda for the Tibetan Government in Exile -- they need all the help they can get until the Chinese get out of Tibet -- and while everything I shot really happened, I obviously shot to show the Tibetans in the best light.
A lot depends on the captions, too, and the Chinese are masters of flatly dishonest captions. You know the sort of thing: 'So and so is starving because of the greedy oppressive lamas' whereas they're starving because Chinese immigrants are getting all the food.
My own inclination is to treat ALL photographs as propaganda, making due allowance for the source (right-wing newspaper, left-wing newspaper, newspaper afraid of offending advertisers...) and to use one's own pictures the same way. Then it becomes a question of how far you trust (or want to believe) the photographer as well as the journal in which his pictures appear.
But I'd still draw the line at 'comping' pictures together or similar heavy digital manipulation: to use Terry Pratchett's words, that's pissing in the fountain of truth.