But until it crashes - Element 115 Missile
and the atom smashes - 115 Explosion
All our minds will just fade away - We'll die and become one of them.
It will end in flashes - The Flashes of the Nuclear Bomb
and we'll choke on Ashes - The Nuclear Fallout
And we'll fall - Human Extinction to Explosion or Radiation
I think this has to do with the ending to Nuketown Zombies. In the ending, you see a Element 115 missile heading for Nuketown. The "it" in The first phrase refers to the missile. The missile crashes to Nuketown and fades to black. Apparently, it means that Nuketown is part of the Moon Easter Egg. Since the missiles are launched on moon, the three missiles are sent to three locations, and Nuketown is one of them. The player is killed/eliminated and the explosion finishes the game, since the missile is filled with Element 115, it would make the players into zombies, thus making things worse. The infection will never be rid of. There is a possibility, like the Syringe, used to revive other players. The cure in the game will never be found, thus making zombies "never-ending". That's my interpretation. Credit to oM(srry, I forgot the rest of ur username). Also, your interpretation was well put and said.