V against n
Verbs with other meanings
There are a number of other verbs which have this pattern.
He warned that the plan could backfire against the allies.
I had toyed with the idea of dyeing my hair black, but decided against it.
I have always saved. And I always like to pay bills as soon as they arrive. My father never saved and perhaps I reacted against that.
In the case of decide, militate, and react, the preposition against is sometimes followed by an '-ing' clause.
backfire battle boomerang chafe decide depreciate harden militate react struggle weigh
We decided against having a midday meal so as to save time.