What does that have to do with anything? The need for a draft is one of several reasons why it is unlikely the US will escalate more. However that is a card the US could play quickly, and combined with the existing military would be enough. (Vietnam could have been won as well, but the US made political choices to not do what it takes)
That's a lot of winning... having to introduce a draft...
How well do you think a draft is going to go? forced on an armed populace that might not want to die in iran?