A surgical stapling instrument, comprising: a handle; a shaft extending from said handle; an end effector extending from said shaft, comprising: a first jaw; and a second jaw rotatable from an open position to a closed position; a firing drive, comprising: a longitudinal rack comprising a longitudinal array of teeth; a firing member coupled to said longitudinal rack, wherein said firing member comprises a first cam configured to engage said first jaw and a second cam configured to engage said second jaw during a closure stroke to move said second jaw into said closed position; an electric motor comprising a rotatable output; and a reciprocatable pawl, wherein said reciprocatable pawl drives said longitudinal rack and said firing member distally a first said stroke length when said reciprocatable pawl is driven distally, and wherein said reciprocatable pawl drives said longitudinal rack and said firing member distally a second said stroke length when said reciprocatable pawl is driven distally a second time; and a retraction knob extending laterally from said longitudinal rack, wherein said longitudinal rack and said firing member are manually retractable said second said stroke length and said first said stroke length when said retraction knob is pulled proximally by a clinician; characterized in that: said reciprocatable pawl is operably coupled with said rotatable output, wherein said reciprocatable pawl is driven distally a stroke length by said electric motor when said electric motor is operated in a first direction, said reciprocatable pawl is retracted proximally relative to said longitudinal rack when said reciprocatable electric motor is operated in an opposite direction, and wherein said reciprocatable pawl is driven distally said stroke length by said electric motor said second time when said electric motor is operated in said first direction once again. a handle; a shaft extending from said handle; an end effector extending from said shaft, comprising: a first jaw; and a second jaw rotatable from an open position to a closed position; a first jaw; and a second jaw rotatable from an open position to a closed position; a firing drive, comprising: a longitudinal rack comprising a longitudinal array of teeth; a firing member coupled to said longitudinal rack, wherein said firing member comprises a first cam configured to engage said first jaw and a second cam configured to engage said second jaw during a closure stroke to move said second jaw into said closed position; an electric motor comprising a rotatable output; and a reciprocatable pawl, wherein said reciprocatable pawl drives said longitudinal rack and said firing member distally a first said stroke length when said reciprocatable pawl is driven distally, and wherein said reciprocatable pawl drives said longitudinal rack and said firing member distally a second said stroke length when said reciprocatable pawl is driven distally a second time; and a longitudinal rack comprising a longitudinal array of teeth; a firing member coupled to said longitudinal rack, wherein said firing member comprises a first cam configured to engage said first jaw and a second cam configured to engage said second jaw during a closure stroke to move said second jaw into said closed position; an electric motor comprising a rotatable output; and a reciprocatable pawl, wherein said reciprocatable pawl drives said longitudinal rack and said firing member distally a first said stroke length when said reciprocatable pawl is driven distally, and wherein said reciprocatable pawl drives said longitudinal rack and said firing member distally a second said stroke length when said reciprocatable pawl is driven distally a second time; and a retraction knob extending laterally from said longitudinal rack, wherein said longitudinal rack and said firing member are manually retractable said second said stroke length and said first said stroke length when said retraction knob is pulled proximally by a clinician; characterized in that: said reciprocatable pawl is operably coupled with said rotatable output, wherein said reciprocatable pawl is driven distally a stroke length by said electric motor when said electric motor is operated in a first direction, said reciprocatable pawl is retracted proximally relative to said longitudinal rack when said reciprocatable electric motor is operated in an opposite direction, and wherein said reciprocatable pawl is driven distally said stroke length by said electric motor said second time when said electric motor is operated in said first direction once again.