Asserting that new recruits to the armed forces must be mentally prepared for the evolving nature of modern conflict, Defence Minister Rajnath Singh on Saturday said major powers no longer hold an edge on the battlefield as even smaller nations can inflict significant damage using specialised tactics. Addressing the Combined Graduation Parade at the Indian Air Force Academy near here, Singh also said emerging technologies have altered the very definition of warfare. "Earlier, it seemed that the big powers had a decisive edge in the battlefield.