‘Nuclear fusion power’ compares the current thermonuclear reactors to fusion reactors. It explains how fusion reactions were common in the early universe and are today the principal source of energy powering stars like our Sun. Fusion reactors are created in the form of hydrogen bombs, each being equivalent to 500 atomic bombs. The search is on for a containment system which would allow controlled civil use of this enormous source of energy. The two options are confinement by magnetic fields and confinement by inertial bombardment. Successful production of fusion would provide unlimited supplies of energy for thousands of years without producing the harmful carbon gases associated with fossil fuel combustion.