What made William Pitt the younger a "giant"?

William Pitt (1759-1806) was dubbed "the Younger" to
distinguish him from his famous father, William Pitt (the Elder)--also a former British
Prime Minister. Pitt the Younger became Prime Minister himself at the age of 24 in 1783.
At first ridiculed because of his youth, he eventually became extremely popular with the
British people, and he was a favorite of King George III. Pitt's honest approach to
government was a refreshing change from the corrupt behavior of previous administrations
and earned him the nickname "Honest Billy." He reorganized the nearly bankrupt East
India Company, solidifying Britain's hold on its colonies in India. He introduced bills 
that supported parliamentary reform and helped to reduce the national debt following the
American Revolution. He sought to form alliances with other European nations in order to
strengthen Britain's power and reduce that of France. Many of Pitt's ideas were thought
to have better prepared England for the tumultuous era of the French Revolution. He
supported the union with Ireland which brought about the United Kingdom of Great
Britain. Resigning as Prime Minister in 1801, he returned to his old position, serving
again from 1804 until 1806. Pitt was pivotal in England's stand against Napoleon, and he
was toasted as the "Saviour of Europe" following England's great naval victory at
Trafalgar. Napoleon's later victories softened Pitt's successes, however, and he died
(probably from a peptic ulcer, due in part for his love of port) in
1806.