That the Bush government planted stories is probably nothing I need to find sources for. That the Obama government does is probably no shock either.

Recently read a good piece.

Glenn Greenwald - Salon.com

Sunstein is currently Obama's head of the Office of Information and Regulatory Affairs where, among other things, he is responsible for "overseeing policies relating to privacy, information quality, and statistical programs."  In 2008, while at Harvard Law School, Sunstein co-wrote a truly pernicious paper proposing that the U.S. Government employ teams of covert agents and pseudo-"independent" advocates to "cognitively infiltrate" online groups and websites -- as well as other activist groups -- which advocate views that Sunstein deems "false conspiracy theories" about the Government.  This would be designed to increase citizens' faith in government officials and undermine the credibility of conspiracists.  The paper's abstract can be read, and the full paper downloaded, here. 

Glenn Greenwald - Salon.com

Consider the recent revelation that the Obama administration has been making very large, undisclosed payments to MIT Professor Jonathan Gruber to provide consultation on the President's health care plan.  With this lucrative arrangement in place, Gruber spent the entire year offering public justifications for Obama's health care plan, typically without disclosing these payments, and far worse, was repeatedly held out by the White House -- falsely -- as an "independent" or "objective" authority.  Obama allies in the media constantly cited Gruber's analysis to support their defenses of the President's plan, and the White House, in turn, then cited those media reports as proof that their plan would succeed.

To prove that the US government is behind stories about unfriendly leaders is hard, but means, motive, opportunity and a pattern of behavior is there.

I am not sure what you meant by "Chavez wouldn't". I bet he would love to plant stories about US leaders but I doubt he has the means.

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