If you want to incentivize military service then make it mandatory and many of the best candidates will enlist in exchange for some influence over their military occupation. If the worker shortage persists, and all indications are it will, this is a probable outcome.
To @downrightmike who thought the Pat Tillman tragedy was worthy of mention in such a disrespectful way, the guy's sacrifice is awe inspiring regardless & your spin on what happened is inaccurate.