The Hornet is an extremely fast gunship designed to quickly destroy priority targets while shrugging off even moderate AA. Lacking the AoE damage potential of bombers, the Hornet's niche lies in penetrating enemy lines to swiftly take out critical units and infrastructure, even under Plasma Deflectors, which cannot stop the Hornet's sabot rockets.
Hornets are very effective at swiftly assassinating Commanders, even those under AA cover.
While they lack the sheer base-killing power of the Blizzard or Liche, Hornets perform extremely well in a surgical strike role, and are much better at killing off scattered mobile units. Too expensive to make in numbers without a late-game economy, Hornets are best used sparingly, and with a fighter screen to protect them from enemy air units.