re: Doomsday Machine (?)
This is a scenario of many SF stories, of either a deliberate or accidental fragmentation catastrophe in Earth orbit leading to the Earth becoming a ringed a planet and denying space to Humankind.
Nasaand the DOD routinely track debris in Earth orbit - you'd be surprised what small items they keep a tally of - down to a few cm or even less.
other web resources
Ultimate Space Debris
Russell D. Hoffman (no relation)