Although Charles Erwin Wilson, the Secretary of Defense at the time, is commonly associated with popularizing the phrase and coining it in the military context, he may not have come up with it himself. Some have pointed out that it bears striking similarity to the 1950s Pepsi slogan "more bounce to the ounce."
It's possible that Wilson took a pop culture cue from the Pepsi ads and adapted their slogan for rampant nuclear warfare. Kind of like how DARPA adapted Nike's "Just Do It" phrase to advocate for chemical warfare. Oh wait, that last bit never happened, because the government stealing a commercial slogan to plug weapons of mass destruction would be fucking insane, wouldn't it?!