By interplanetary space, we are talking about an environment in which space radiation is much more intense than it is in LEO, because above Earth orbit is the geomagnetosphere, the Van Allen belts, which trap charged particle radiation coming from deep space.
Be it a better mouse trap or a newly crafted strategic policy built in an era of deep and painful cuts in military spending, the budget necessities facing all Americans demand a level of frugality not seen during the lifetimes of many of those now in uniform.