Jelman9099 wrote:You could pay to not be selected for it. They had a code for it even.
That was the Civil War you're thinking of friend. Read the article you posted. In vietnam, it was deferred for students. And while greenbacks wouldn't legally get you out of the draft, money and influence certainly meant you were more likely to get a choice spot in the National Guard (it's alluded to in the article you linked).
On topic: Vietnam; WWII; WWI. Before that, who knows. After that, it became politically expedient to do away with the draft.