A motor-driven surgical cutting and fastening instrument that comprises an end effector, a shaft connected to the end effector, and handle connected to the shaft. The end effector may comprise a cutting instrument that, when actuated, longitudinally traverses the end effector to cut tissue clamped in the end effector. The handle may comprise an electric motor for actuating the cutting instrument and a motor control circuit for controlling the motor. The motor control circuit may comprise a power source connected to the motor for electrically powering the motor and a current control circuit, connected to the power source, for varying the current supplied to the motor from the power source. The current control circuit may vary the current supplied to the motor, and consequently, the output torque supplied by the motor, such that the motor has at least (i) a first, low power operational mode for a first portion of a cutting stroke cycle of the cutting instrument, and (ii) a second, high power operational mode for a second portion the cutting stroke cycle of the cutting instrument.