That 4.2 million people included all the military and civilian contractors, unable to be hired because they are fulfilling their roles. Additionally that 4.2 million includes all clearance levels. The higher the clearance, the more the available talent pool SHARPLY declines. I have first hand info, AWS is DESPERATE for cleared individuals for various contracts. Unfortunately the recruiting has not synchronized their offers with this need, so you get a lot of low balling offers that most cleared people laugh at.