The questions are what race and why.
Fallout 1 - a survivor of the nuclear war falls into a vat of military virus that transforms him, making him stronger and smarter, and granting him psionic abilities. The Master thinks that the NEW race is the future, since they are better suited to the PA life. The Unity thing will "finally eliminate the differences and the human fallacies that ultimately brought about the nuclear war."
Fallout 2 - the President wants to eradicate all mutants, and since most life is mutated, it means that he wants to destroy all life on the planet. You'd think that a strong faction that managed to survive the post-apocalypse would have better things to do than trying to exterminate what's left of life in the fucking wasteland. Like, seriously. It doesn't make sense. I can see him thinking that the pure humans are the new master race and all mutants, even the ones that look normal, are sub-humans and slaves, and the Enclave would need a lot of slaves to start rebuilding, but that's not the case, which is why their plan is nothing but "we want to destroy all life because we are teh evil!"