
Nope, you're confusing separate programs.  Atlas was the first-generation
US ICBM; Titan I was the second-generation one; Titan II, which all the
Titan launchers are based on, was the third-generation heavy ICBM.  There
was essentially nothing in common between these three programs.

(Yes, *three* programs.  Despite the similarity of names, Titan I and
Titan II were completely different missiles.  They didn't even use the
same fuels, never mind the same launch facilities.)
