United States of Smash is the most powerful technique in All Might's vast arsenal. It is a smash attack that concentrates all of One For All's remaining power into All Might's fist.
All Might delivers an incredibly powerful punch and smashes his target into the ground. The attack appears to compile the strength of All Might's other smash attacks into one spectacular move.
The impact of this smash is so strong that, upon striking All For One, the wind pressure created from its delivery left a massive crater in the ground and spawned a twister strong enough to carry nearby buildings.
The surge of power received was so powerful that All Might's damaged right arm was quickly restored to full strength, albeit only for a single blow.
A variation of this technique called United States of World Smash was later inherited by Izuku and used in his battle against Flect Turn. The technique was powerful enough to completely negate his Reflect Quirk and cause insane collateral damage around them. In this version, Izuku first unleashes a series of punches at 100% to pulverize his target and then moves around them at blinding speeds in order to build momentum and air pressure. He then launches himself towards the target and uses the air pressure and momentum to deliver a devastating kick.
- United States of Smash is featured as Toshinori's ultimate move in Jump Force.