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In any Star Trek canon, was warp technology ever used to intentionally damage something? According to physics as we know it, the ability to deliver a payload (even a relatively small one) at relativistic speeds would be devastating to virtually any target (trust me, don't stand in the way of the LHC beam). Since warp drive allows ships to travel even faster than light, one would think that would only increase the damage it could do if slammed into another ship.
Was warp drive ever used to propel a projectile (or even a full ship) into a target? If no, is there any reason given as to why not?