What is Astroturfing?

Astroturfing is a manufactured, coordinated "grassroots" effort made to look organic. An organic grassroot movement is created at the bottom of a movement - when like-minded people get together and lobby for or against a particular cause. An Astroturf movement is created from the top where a group of powerful people organize individuals to help sell what they want done.

So based on this, would the President and DNC sending an email to it members to encourage them to work on behalf of the President and his administration to sell his health care plan be a grassroot effort or astroturfing?

I thought protesting was used by people to protest their government. We now have a government protesting against the people. Am I the only one who finds that disturbing?

UPDATE: More on this over at Hot Air.
UPDATE II: Ace has a post about Congressmen having "virtual townhall meetings" and makes the point: That's fine if you don't mind being a "virtual" Congressman come January 2011.