Spectral lines: 'The challenge of all time'

Lest anyone suppose that there is a holistic logic to the concept of the Strategic Defense Initiative (SDI), rest assured that there is not. That is because the scenarios, time frames, weapons, and even the "players" are still unknown or ill-defined. The best that can be said is that, in the minds of many of the most informed scholars of military strategy, the United States has no better alternative. The investment in the SDI is a necessity, they believe.