Midway had value beyond the Doolittle Raid

Would Japan still have attacked Midway without the Doolittle Raid?

Probably eventually; the raid accelerated the decision, but Midway was independently attractive to Japanese planners.

The answer pushes back against a single-cause explanation for Midway. The Doolittle Raid mattered politically and helped Japanese advocates overcome resistance to the operation. Midway’s location was nevertheless attractive in its own right as a forward position near Hawaii and along the approaches to the central Pacific. Japan could therefore have targeted the island later even without the raid. The raid accelerated a decision about an island that already held strategic interest.