Apparently, the US military used a PDF file to publish the report relating to the death of an Italian agent (Nicola Capilari) and the wounding of Guiliana Sgrena . In that report, many items had been blacked out (redacted) because of security concerns. Unfortunately, the military personnel who ensured the classification of those items don't understand the properties of Adobe Acrobat very well. The redacted items are easily pulled from the report. I've read the whole piece, and, in my opinion, many of those items should remain hidden, blackened, redacted, etc.
The report contains some material that had been blackened that may seem trivial to some. Michelle Malkin has a great post about this, and she's correct about how wrong the gloating left can be about these things.
Kevin Drum of Washington Monthly demonstrates his lack of understanding of why this information should not be made publicly available:
...Another section describes the methods used by insurgents to place bombs along "Route Irish," the road to the Baghdad airport, including: positioning explosives alongside guard rails, staging equipment in vehicles or near overpasses, wrapping explosives in brown paper bags, using timers, etc. I can't imagine that this stuff is even remotely worth classifying, since these techniques are obvious to anyone who thinks about how to place explosives for more than a minute or two, but for some reason they were redacted...
Actually, if the enemy had this information before the report was "opened", it confirms to the enemy that the information that they had is correct. There are many reasons why this is bad - one being that they don't have to expend resources confirming it now. If they didn't have the information, they do now - another reason that this is not good for our troops is that you couldn't possibly know what information you just are giving away...
Por ejemplo, your house was robbed the night before and the thieves took all of your electronics. That could be because it's easier to fence electronics or it could be because they didn't know where your jewels were hidden. Then, during an interview with a reporter, you say, "But at least they didn't get the diamonds hidden under the bed."
Did you just give away information that the thieves already had? Or not?
How would you know?
Update: Austin Bay's analysis is dead-on.