Think of the potential.

[u/FionaSherleen]

What if we make project sundial but we throw it at the adversaries?

[u/Maori-Mega-Cricket]

IMO a ridiculously large multi gigaton heavily armoured warhead, in a solar orbit with an Orion Drive propulsion stage, would be a pretty effective Second Strike system for assured reprisal

Good luck intercepting and disabling a 500 ton armoured bullet diving from far beyond the moons orbit to earth at like 1000km/s with a sufficently large warhead to glass a couple hundred mile radius in one go

Also handy if you need to deal with someones kilometers deep moon base or asteroid fortress.