Pretty cool! An excellent Jam-Game.
It is a little bit of an anti-game though. The sides are so evenly matched that the war sustains itself with little player input usually.
The cards don't make much of a difference since the units die so quickly and the cards cost so much.
There is also a glitch/balance issue after level 15, where the AI appear unwilling to win. Even spending all of your cards on one side will not make it win, and eventually you have two level 20 sides with thousands of dollars they won't spend quickly enough. Eventually the game crashes.