I have a feeling this is going to become a staple pretty fast, and is universally useful almost everywhere.

Pros

-4 credits is basically a reverse Sure Gamble

Comes without the clunkiness of Reversed Accounts

Run condition will be easy to satisfy

Can be part of a larger combo- Hard-Hitting News becomes easier to land, and a single use of Ewar saves you 8 credits over a double Punitive Counterstrike play

Can be used in pairs of double the pain, or kick the runner while they're down, especially in Spark Agency: Worldswide Reach.

Brutal in conjunction with the "-6" cards like Bryan Stinson, Observe and Destroy, and Manta Grid/Nihongai Grid.

Cons

Clogs up the hand while waiting for other pieces, may lead to wastage- 2 is probably the most copies you want

Overall this is a very scary card and will probably change the runner's game once they see it.

By itself, this is a reverse Hedge Fund, and could be justified on that basis. But it is wildly more effective than Hedge Fund for setting up trace operations, usually Hard-Hitting News. A Hedge Fund allows you to spend up to $4 more to seal a trace, but any money spent then evaporates. Economic Warfare saves you up to $4 on what you need to spend to seal the trace, and the runner takes a $4 loss which does NOT evaporate. The credit swing of Economic Warfare on a HHN turn is usually $8, which is excellent.

Tactics: Hard-Hitting News players will probably hold this card ~exclusively for a HHN turn. If your deck doesn't have HHN, Economic Warfare should usually be played on first opportunity. (Early losses compound and make it harder for the runner to play economic cards like Daily Casts and Sure Gamble. Draining their credits early may even force several clicks-for-credits which is more impactful than a later $4 loss on a runner that's already set up).