It is often said that that recruits enter the service as boys and leave as men. My Korean-War-era dad said as much about his own experience and thought that everyone would benefit from two years in the service.
Perhaps, we need to start an aggressive new "Reserve Corp" that will act as a finishing school of sorts in the US Military environment. Youth unemployment, particularly among minorities, is very high and there is much work that can be done in our cities and small towns (AFSCME won't be happy). The new corp ought to have lower admission standards than the regular military and offer half the pay. Build new Quonset huts across the country on excess federal property to house those for their two-year hitch.
The New Corp personnel would go through basic military training - just as the regular service - and go on to learn useful trades in today's economy. Basic remedial education would be available so that those without GED's will get them during their service and be able to continue to college after their service, should they wish. If they have a particularly successful two years, members could transfer to the regular military for a career.
Meanwhile, our infrastructure would benefit from the myriad repairs and improvements that New Corp would regularly provide in it's basic mission. We would have many more men and women under arms should the need arise. Social engineering? Yes - the best possible kind and a bargain for taxpayers by any measure.