Anticipation in itself is not an action word it defines a state of mind. One can act in anticipation but the action remains undefined as to whether that action is proactive or reactive.
Example: If I am anticipating a punch from you I can either act with “proactive interference” by punching you first or I can wait for your punch and react to it by blocking it then punch.
Now I am sure you can define proactive out of existence so the word needs a modifier like “proactive inhibition” or "proactive interference”. I would guess the only truly proactive action would be instinctual, primal, or pre-programmed one.
This is getting away from the point. My original assertion was that foreign policy is inherently reactive.