Whilst I have agreed to disagree with Old Holborn over the Israel and Palestine situation, there is another point of ethics to consider.
You see, I'm kind of old-fashioned and I do tend to think that if you post a graphic video that purports to show Israelis blowing Palestinian civilians to shit and it is actually a film of Hamas' own rockets exploding during one of their rallies, then you should probably admit that you made a mistake.
Apart from anything else, not to do so damages one's credibility—which is, after all, what a blogger's reputation hangs on...
Yes, I do try to admit my errors of fact. "Errors" of opinion?—no. Those are my opinions and you can like 'em or lump 'em. Although I do listen to counter-arguments too: otherwise, what would be the point of soliciting feedback...?