Operation Defense, or #OpDefense as mentioned on Twitter, stems from Anonymous' opposition to the proposed Cyber Intelligence Sharing and Protection Act (CISPA), a bill that would enable private companies and the government to more easily share cybersecurity information.
Anonymous announced "Tango Down boeing.com by #Anonymous for #OpDefense" on its YourAnonNews Twitter feed at about 3:45 p.m. EDT Tuesday,(msnbc)
We will not allow you to attack our home. The Internet will perish when we perish...and we will never perish. You are weak and will therefore die.(The anonmessage)