If a missile is flying at Hypersonic speeds would the missile need an Explosive warhead or could a Depleted Uranium or tungsten penetrator do the required damage?
With a Non explosive warhead the missile should fly faster still because it could weigh less.
You want a lot of damage on the target all at once
(big hole in the hull or massive damage to the superstructure). An inert penetrator would not generally do that. Indeed, it might create a hole and pass through the ship completely. Lots of examples of this from history - see accounts of using AP ammunition against lightly armored ships.
DARPA is running this hypersonic project, which may explain why it’s progressing better than the Air Force’s AGM-183A. According to the agency (and various experts), the scramjet hypersonic missile has “plenty of kinetic power” without a warhead. Makes sense; anything flying at Mach 5+ slamming into something is going to inflict devastating damage, if not destroy the target outright....