The bare bones tools for a cyber-attack are to identify a vulnerability in the system you want to gain access to or you want to subvert or you want to deny, destroy, or degrade, and then to exploit it, which means to send codes, deliver code to that system somehow and get that code to that vulnerability, to that crack in their wall, jam it in there, and then have it execute.

We've learned that we've allowed technological capabilities to dictate policies and practices, rather than ensuring that our laws and values guide our technological capabilities.

While the US Constitution marks these programs as illegal, my government argues that secret court rulings, which the world is not permitted to see, somehow legitimize an illegal affair. These rulings simply corrupt the most basic notion of justice - that it must be seen to be done. The immoral cannot be made moral through the use of secret law.

The government doesn't want us to know what they're doing, how they're interpreting the law, how they're interpreting and redefining their powers, and increasingly, how they're redefining the boundaries of our rights and our liberties, broadly, socially, and categorically without our involvement.

We're now more than a year since my NSA revelations, and despite numerous hours of testimony before Congress, despite tons of off-the-record quotes from anonymous officials who have an ax to grind, not a single US official, not a single representative of the United States government, has ever pointed to a single case of individualized harm caused by these revelations. This, despite the fact that former NSA director Keith Alexander said this would cause grave and irrevocable harm to the nation.

The majority of terrorist attacks that have been disrupted in the United States have been disrupted due to things like the Time Square bomber, who was caught by a hotdog vendor, not a mass surveillance program, not a cyber-espionage campaign.

I have had many opportunities to flee HK, but I would rather stay and fight the United States government in the courts, because I have faith in Hong Kong's rule of law.