No the Eugenics wars were endeded well before the nuclear holocaust of WWIII. When you see Zephram Cochran in First Contact, it was many years after Earth was d

No the Eugenics wars were endeded well before the nuclear holocaust of WWIII. When you see Zephram Cochran in First Contact, it was many years after Earth was devastated by nuclear winter. That's why populations were sparse, and there were various warring sects all over the world fighting for power. The warp drive (and discovery of aliens) is what united humanity after all the wars.