There isn't a specific "war's sword" that universally represents all wars. Swords have been used in countless wars throughout history, and there are numerous types and styles of swords associated with different cultures, time periods, and conflicts.

For example, in European history, swords such as the longsword, arming sword, and broadsword were commonly used in medieval and Renaissance warfare. In Japan, the katana played a significant role in feudal conflicts. Other cultures had their own distinct sword designs and styles that were employed in warfare.

Additionally, the specific swords used in war varied depending on the role and social status of the warriors. Different soldiers and warriors may have wielded swords specific to their function, such as cavalry sabers, officer's swords, or infantry swords.

It's important to recognize that the idea of a singular sword representing all wars is a generalization, as swords were diverse and varied across cultures and time periods.