In The Danger Of The Low-Cost Cruise Missile, Bruce Simpson explains how it doesn’t take much to build a cruise missile these days:
However, during the past decade, huge strides have been made in commercializing much of the technology on which the cruise missile is based and it is my firm belief that building a low-cost, autonomous, self-guided, air-breathing missile with a significant payload capability is now well within the reach of almost any person or small group of persons with the necessary knowledge and skills.
In fact, he has started a project to build a cruise missile for under $5,000, and he has started a project diary.