In general, this statement is true in the sense that Truman was a pragmatic leader. He of course came into office because of FDR's death, so he had great shoes to fill. Yet he did so with great poise.
For 391 years, going from 794 to 1185, the real power in Japan was in the hands of the Fujiwara family (A option), they achieved that by monopolizing regent positions. The seize of power by abdicated emperors at the 11th century followed by the rise of the Samurais led to Fujiwara's gradual decline.
Went in to the war and dropped an atomic bomb on Hiroshima
B. I remember doing this and this made me type 20 letters