YouTube - Collateral Murder - Wikileaks - Iraq
Yes, I know it is hard to see at these distances. If you're not sure, don't shoot! Okay, so, I guess that they were sure - and deluded.
ETA (from a comment below): Update on the video - response from US Secretary of Defense: http://news.yahoo.com/s/nm/20100411/pl_nm/us_iraq_usa_journalists