GEN1367 How did Jacob prepare for war?   Rashi and other commentaries, based on the text, say that he prepared in three distinct ways: through gifts of appeasement for Esau Genesis 32:14-21, through prayer Genesis 32:10-13, and through preparations for actual battle Genesis 32:8-9.  Thus, we can infer that these three preparations are legitimate Jewish methods of readying for and fighting a war.   The first step is to try to avoid war completely by trying to appease the adversary, if possible.  Simultaneously, Jews should pray for God’s assistance to avert the war or for victory, and this is also a legitimate means of fighting war.   Since the outcome of the war is ultimately in the hands of the Almighty, heartfelt prayer (and Torah learning) can have an impact on the war’s outcome. … Only when all other tactics failed to prevent war was Jacob prepared to fight.  AMEMEI 307-8