The United States is upgrading its nuclear arsenal at about $20 million a warhead. In order to get an impactor with, let's say, 100kt of kinetic energy (decent medium sized yield) you'd need somewhere around 160,000 kg of material smacking into the Earth at reentry speeds. That's three launches of a Falcon Heavy to get the material into LEO at a price tag of almost $300mil.
karl2025 t1_ja105we wrote
Reply to comment by underthingy in TIL there's a rock formation in Saudi Arabia about 6 meters high and 9 meters wide, split curiously in half and balanced on two small, natural pedestals. The origin of the Al Naslaa rock formation is unknown. by OccludedFug
Ottoman.