I think his firing is a good thing. It maybe will send the message that misrepresenting new coverage might not be tolerated. In this case it was pretty irrelevant to any message, but was done for aesthetic reasons.
Photographs and especially news photographs of a war are powerful images and often carry an indelible message. Any manipulation of this should not be tolerated. Time magazines cover of OJ Simpson making him look dark and evil
(although to some he is dark and evil) was highly criticized and the photographer or art director said that they considered it an illustration so it was ok. Nobody agreed with them and Time later apologised. An illustration or artwork is allowed this point of view but a photograph is not supposed to lie.
I agree that in the past news photographs have been messed with but with photoshop it is a pretty flawless process and I think his firing sends a good messsage. If you can't take a great news photograph get another job.
Just my opinion