At the point where hacking isn't really considered an act of war. Obviously neither side actually does consider it an act of war, or else they wouldn't dare. If "hacking is considered an act of war" were ever a bluff, then it has been thoroughly called long ago.
Anyone enthused about going to war against China about this? Anyone? Anyone? Nope. I guess it's not going to happen then.
And of course I think we can only assume that the US is hacking 'em back.
It's like spying. It's officially against "the rules", and everybody acts shocked, shocked when they catch foreign spies within their country, but everybody is constantly doing it to everybody and everybody knows it.
"Hacking" is like "terrorism"; it's not an end state. It's "spying" when it's done for "spying". It's an "act of war" when it's done to shut down the power grid.
Nowhere. It's already generally understand by the U.S. government/military that anything on any computer connected to the Internet is public. Unless they decide to crash our power grid or meltdown some of our nuclear reactors then no one is going to do anything, unless it becomes politically convenient for propaganda purposes at some point in the future.
