Want to improve national security without spending billions on a new weapons system? Slim down America's kids and teach them to read, some retired generals say.

The Army says more than three-fourths of 17- to 24-year-olds today are not eligible to join the military because they aren't fit enough or don't meet other basic requirements, such as having a high school diploma or being able to read or write properly.

That's got some of the nation's highest-ranking retired military officials advocating a radical way to improve national security—improve the lives of children.

"It's not just a school problem. It's not just a Department (of Education) problem. It's a national security issue and it needs to be prioritized that way," said retired Maj. Gen. D. Allen Youngman.

He's one of hundreds of former military officers who have gotten involved in Mission: Readiness, a nonprofit organization whose "Too Fat to Fight" reports attack junk food in schools. Its members also lobby lawmakers for improved school lunches and more widely available pre-K education.

These military officials say such interventions are necessary for increasing the pool of people who want to serve in the military and would be able to do so.

"If you have a very small (group) who are interested to begin with, and then the majority are not qualified, you can get into a pickle quickly," Youngman said.

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