Originally Posted by narutorikudoumode
hashirama has to have some thing he regretted no one would think he did it
wouldn't it be more awesome for the story if hashirama actually pwned madara at VoTE but he was unable to kill him. (a parallel to the naruto-sasuke battle @ VoTE). He could've let him live, even giving him some of his regenerating blood at the cost of banishing him from the village. Hashirama could've lied that he killed madara. Madara was so humiliated by his defeat thus he wasn't able to return/retaliate against the village as long as Hashirama (or others who know the secret) lived.
That would be something Hashirama could regret... and a better story to aid the "Bonds" theme of the manga.