Of it being all right to lie if the cause is right. Witness the ENTIRE Iraq campaign.
Frankly, I personally didn't see ANY misrepresentation of actual fact in Moore's movie. But there is no question that he used cinematography tricks to make various Bush admin people look foolish for no purpose but ridicule. And I wish that he didn't, because, frankly, it discredits the ACTUAL message in Moore's film, which happens to be generally accurate and valid.
But, in all candor, there was not a snowball's chance in hell that the Right wing would not have smeared Moore even if his film was SCRUPULOUSLY honest and even-handed. And, BTW, while it is most certainly NOT even-handed, it is also NOT dishonest in it's content - just like a biased political commentary one might hear CNN Crossfire, or read in an editorial - Those are all completely valid without being even-handed. We know this for a fact, because the attacks began WELL ahead of the actual film, down to the major effort to censor it well before anyone knew what was actually in it. That, BTW, is a simple disregard for the 1st Amendment.
And, incidentally, I view this as no different from a Bush or Kerry campaign Ad. Everyone knows that they are biased, and in many cases, they are downright dishonest (especially much of Bush's recent Ads that ran a couple of months ago). But, plain and simple, EVEN if they are dishonest, and most assuredly, many of Bush's ads WERE, the fact is, they are protected speech under our Constitution, and it is up to the other side to convincingly rebut the arguments being made.