While a suspect responsible for the Boston Marathon bombing has yet to be determined, The Washing Post points out that a publication called The Anarchist Cookbook provides written instructions for making homemade pressure cooker bombs, like those used in Monday's attack, and has been in print circulation since 1971.
The book was written by William Powell to protest the United States involvement in the Vietnam War and contains the instructions for the manufacture of explosives and other anarchist devices. The book is thought to have provided the instructions for at least one bombing in 1976 at Grand Central Station. Since its publication, the writer has fought to get it out of print circulation since he no longer advocates the information in the book.
Today, The Anarchist Cookbook is not the only source to get instructions on how to make homemade bombs. In 2010, members of the Yemen-based branch of al-Qaeda published an electronic magazine called Inspire, which features an article that gives the instructions on how to build a homemade bomb out of a pressure cooker.
Although the al-Qaeda publication has provided the information to make the same bombs as the ones used in the attack at the Boston Marathon on Monday, nothing about it gives sufficient evidence that al-Qaeda is behind it. According to The Washington Post, the issue of the magazine was downloaded more than 5,000 times and stretched to the far corners of the internet. There is even a subculture in America of building small pressure cookers for the purpose of blowing up for recreation in empty fields and posting videos of the explosion on Youtube.
However, as far as any of this goes, neither publication helps the FBI catch the person or group responsible for the Boston Marathon boming.