By Danielle Leigh
NBC News
The controversial book detailing the mission that killed Osama Bin Laden hit shelves Tuesday.
More than a half-million copies of "No Easy Day" have already been released, even though the Department of Defense says some of the details included in the book never should have been released.
The book is written by a former Navy SEAL who claims to be one of the first through the door during the raid that killed Bin Laden.
The Pentagon says the author is revealing secret information and should have allowed the Department of Defense to pre-screen the book before its release.
Military experts fear the memoir could put other servicemen in danger.
"They don't want their faces or names known. They don't want their techniques understood," says NBC military analyst General Barry McCaffrey.
While the Pentagon considers legal action, those sensitive details are making their way into the hands of curious readers like Stacey Lloyd.
"From a human point I would like to know what motivated this fellow in writing this story," Lloyd says.
The author disagrees with the Pentagon.
He says he hasn't violated any vows of secrecy or revealed any information that will put his colleagues at risk.
