The 1967 treaty banning the deployment of nuclear, biological, and chemical weapons in space did not envision the United States finding an easy way to get around it. The method consisted in the fact that a bunch of tungsten rods as thick as a telegraph pole are dropped from space to Earth, which, as they approach the surface, reach hypersonic speed (up to Mach 10), acquiring a destructive force comparable to ICBM warheads.
During the Vietnam War, the United States used bombs called "Lazy Dogs", which are ribbed metal needles about 5 cm long, sharpened on both sides. Dropped into the jungle from planes in huge numbers, they left nothing alive in the places where they fell.
Lazy Dog shells, falling from a height of only 1000 meters, reached speeds of over 800 km / h, piercing concrete floors 25 cm thick.
This concept was developed in another program of the Pentagon during the Cold War - Project Thor. Within its framework, scientists studied the possibility of hitting ground targets with tungsten projectiles, which they dubbed the "Rods of God." A tungsten blank dropped to Earth could easily destroy buried objects, which would be accompanied by a giant explosion, comparable in power to a nuclear one, but without its destructive side effects.
Fortunately, this idea never materialized due to the enormous cost of the project. As one of its participants admitted, the cost of one space shot with a weight of 11 tons of ammunition would have cost $ 230 million, which was an exorbitant amount during the Cold War. It is no longer so fantastic these days.