Kinetic energy would have the best place against stationary targets, like mortar fire is in the modern era. Space stations and planets. You can calculate rotations and orbits, and deceleration is nearly zero in a vaccuum, so you can fire near-light railgun shots from years away, to completely kill a planet from several directions, nearly undetectable given their small size and speed.

A laser's energy would dissipate over those distances, the aggression would be obvious, but kinetic weapons could sentence a genocide to a world before the world even knows a war is declared, the politicians could still be on trading and speaking terms for years while one side knows the killing blow is already inbound.