[dragoon500ly]

How many people would need to be drafted?

The easy answer is a lot! With the need to recruit service members to bring units up to TO&E strength, among all five branches, then you are looking at hundreds of thousands. Toss in the Reseve and Guard units, and you are looking at potentially a million or more.

The best example is World War Two, many people don't realize that the US military started ramping up for the war almost two years in advance, bringing Regular units to full strength, building/expanding training and support facilities, registration for the draft and then calling up the first draftees.

It is generally considered that roughly 17 weeks is needed to take a civilian, complete basic training and then push the new soldier through AIT, in the end, you have an individual that has a basic idea of their job, but is sorely lacking in experience. It takes roughly a year, in a peacetime Army, to get that new soldier sufficient experience for them to be an useful part of the unit. In wartime, running 7-days a week training schedules and exercises, you can get this done to roughly 6 months.

And by this time, you have a shooting war on three continents, with modern weapons being employed, casualties will be brutal. There will be demands to get these new recruits to the fighting units to bring battered divisions back up to effective strength. Give these new recruits experience? Again, the WWII experience gives us a horrific view of what happens next, green 18-year olds reporting to their new unit, just in time for tomorrow's offensive, their squad leaders not even able to learn their names before they become casualties. Toss in the "joys" of a chemical attack and those new recruits are decimated, time for the G-1 to scream for more replacements.

By time the strategic nukes start getting tossed, I would expect that the replacement pipeline would be drying up, unable to sustain the heavy demands. This is why I can see divisions shrinking down to only a few thousand soldiers. Senior commanders would have no choice but to ruthlessly comb through support units in order to scrap up enough soldiers to reinforce the front. Air Force and Navy units, there are no aircraft or ships left! Welcome to the PBI!!