Railguns as a possible close-range layer

Could future naval procurement include eight-inch guns with smart shells as a cheaper alternative to missiles?

Yes, depending on gun range. Railguns reaching roughly 200-300 miles could handle nearer targets while missiles retain the longer-range role.

The usefulness of large guns with smart shells depends on the range they can achieve. If railguns enter service and can hit targets roughly 200-300 miles away, they could handle nearer targets while missiles cover greater distances.