One of Yes Man's Securitron avatars turns towards you as you both stand on a cliff overlooking the second battle of the dam.

"This is the grand finale, everything you've been working for! How exciting! Don't let me tell you what you already know but I just wanted to remind you that there are two choices for wrapping up this battle. You can either destroy the generators in the dam, rendering it a giant concrete wall, or you can route the power to fortification hill and use the securitrons to push the NCR and Legion right out of the Mojave!"

The Bear and the Bull, ideological enemies but perhaps more similar than either would care to admit.

NCR
>I befriended the NCR and helped wherever I could with them, particularly in dealing with the legion this side of the Colorado. (Completed all NCR side quests)
>They were never a priority for me, even after I committed myself to Yes Man and an independent New Vegas. I am an unknown variable in their eyes.
>The only thing an NCR conscript feared more than a Centurion was me. I wreaked havoc across NCR territory, killing all who dared carry the flag of the bear.
> My relationship with the NCR was….[Write in]
Caesar’s Legion
>I proudly carried the symbol of the bull on my armor as I carried out Caesar’s will across the Mojave. Up until I betrayed him at the battle of the dam, of course. (Completed all Legion side quests)
>What I heard about the legion, both good and bad, didn’t grab my attention. I threw the “mark of Caesar” into the Colorado when I needed to free up carrying weight.
>A dying legionary once told me I would have made for a fearsome Legate. Well, I think he said Legate. I blew his legs off before he could finish his sentence.
>The Legion? [Write in]