While (according to my understanding) War theroticians have not concluded adequately when a cyber-attack can be answered with the use of kinetic force, especially in the case of non-state actors, a new question emerges:
– When a non-state actor (or even a state one) attacks my Economy, is the use of kinetic (or other) force a justified act of defense?
Managing organized complexity 
First we have to define what an attack to the economy is.
Thanks to the “War on terror” this is pretty much a solved question. The “I know it when I see it” principle applies. There is actually no need for a strict definition of an attack on any battlefield dimension. That is why not all kinetic incidents are considered as attacks too. So when a consensus of those who matter, consider something as an attack, then it is an attack.
But even if you do not like what I think about what an attack is, observe that neither UN’s Article 51, nor NATO’s Article 5 (who both deal with kinetic attacks) define what an actual attack is. The case of invoking Article 5 after 9/11 (and after consulting with other alliance members) -the only case of invoking it- is highly educating on defining what an attack is.
I think it is also interesting to note that “Unrestricted Warfare” (published in 1999) asks the same question (page 12):
I also think the question of what constitutes an attack is a valid one. Some variables that show how difficult it is to define the problem:
Who is the attacker? Is the economic disruption due to a terrorist manipulating the market or a profiteer that plays hard, or (worst case) the automatic trading systems going crazy? Hard to tell.
Then what is the purpose of the attack? Disruption of western society by a terrorist group? Rival state gains? Who would absolutely gain from that? (the Law of Unintended Consequences in a globalized market….)
Timeline? With some economic measures the effects are very slow but very real. In the early 90’s the US allowed the dollar to fall to hurt the Japanese economy. Did THAT constitute an attack?
And let’s not forget. Many times the states manipulate their economic figures towards their geopolitical goals: the Chinese control RMB rates.
In the past (19th and 20th centuries) the states issued ultimata, and went to war over economic issues. Right now, it seems to me, it’s just “Rules of the Game”.
We follow an economic system that by its way of operation may lead to unfavorable results. Should we consider the economy under attack when it’s not suiting us?
I wonder if there could even be such a thing as an “Economic Attack” (from non-state actors). If we accept there could be, then should we see states retaliating (with a kinetic attack!) to a bad credit rating?
As an end note I browsed through the Presidential Directives for the US Dept. of Homeland Security (http://www.dhs.gov/xabout/laws/editorial_0607.shtm). The economy is considered only from the point of view of preserving Critical Infrastructures. Make sure the Wall St. is open. Inside, everything goes…
Ultimata are about formal declaration of War between state actors. They are not about attacks.
Keep in mind though that non-state actors were essentially attacking state economies, even in the old days: Pirates are a fine example. And affected states defended themselves against them with military campaigns, and paying ransom and even treaties. Let us also not forget that at times, Pirates (non-state actors) were covertly funded by rival governments in order to avoid attribution and direct conflict. Much like what many say about a certain government and its ties to its digital underground, whose cyber attacks cannot be attributed back to a government.
“Inside everything goes”
I think the SEC (among others) disagrees with this statement.
Nice parallel: Pirates-Today’s attackers.
As for “everything goes”, it’s “everything” within the rules…
As for what constitutes an attack, can we answer with yes/no with every example I mentioned? (e.g. let the home currency fall, control the exchange rate of home currency, degrade the credit rating of a country etc). If we can, we may come a step closer to understanding what is an attack in economic terms.
I used Pirates as an example, because it is still happening. Governments negotiating with them for hostages using ransom, or even commandos and Navy to protect commercial Navy ships.
The funny thing with the rules is that they keep changing, because the key players always seek ways to bend them. It is an evolutionary process I guess.
As to agreeing what constitutes an attack, it does not really matter whether we agree or not. There exist certain authorities that declare this (KYSEA for Greece) and we do not participate. I can only argue that the surrounding context, economic and political environment can help us decide whether a certain event is an attack or not.
Which ‘certain government’?
“Inside Cyber Warfare” makes extensive commentary on the practices employed by the USA, Russia and China. Make a wild guess :)