When Edward Snowden revealed that the NSA has been doing exactly the same thing as the Chinese to computer networks around the world, we used much more moderate language to describe U.S. actions: words like espionage, or intelligence gathering, or spying. We stressed that it's a peacetime activity, and that everyone does it.
The reality is somewhere in the middle, and the problem is that our intuitions are based on history.
In other words, it's hacking. Cyber-espionage is a form of cyber-attack. It's an offensive action. It violates the sovereignty of another country, and we're doing it with far too little consideration of its diplomatic and geopolitical costs.
By Bruce Schneier
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