Question: The country of citizenship of the author of The Boy Who Reversed Himself lost the most soldiers in what war?

full_context: Document 1: William Sleator: William Warner Sleator III (February 13, 1945 – August 3, 2011), known as William Sleator, was an American science fiction author who wrote primarily young adult novels but also wrote for younger readers. His books typically deal with adolescents coming across a peculiar phenomenon related to an element of theoretical science, then trying to deal with the situation. The theme of family relationships, especially between siblings, is frequently intertwined with the science fiction plotline.
Document 2: Son of Man (novel): Son of Man is a science fiction novel by American writer Robert Silverberg, published in 1971. The book is about Clay, a 20th-century man, who travels billions of years into the future and meets humanity in its future forms. Some of the issues discussed in the book are sexuality, telepathic communication between people, physical prowess or frailty, division of humans by caste or ability, and the preservation of ancient wisdom, among other things.
Document 3: Muslim world: Theologus Autodidactus, written by the Arabian polymath Ibn al-Nafis (1213–1288), is the first example of a science fiction novel. It deals with various science fiction elements such as spontaneous generation, futurology, the end of the world and doomsday, resurrection, and the afterlife. Rather than giving supernatural or mythological explanations for these events, Ibn al-Nafis attempted to explain these plot elements using the scientific knowledge of biology, astronomy, cosmology and geology known in his time. Ibn al-Nafis' fiction explained Islamic religious teachings via science and Islamic philosophy.
Document 4: The Green Futures of Tycho: The Green Futures of Tycho is a 1981 science fiction novel for young audiences by William Sleator. The book explores the effect of excessive parent expectations on the future of their children.
Document 5: Interstellar Pig: Interstellar Pig, published in 1984 by Bantam Books, is a science fiction novel for young adults written by William Sleator. It was listed as an ALA Notable Book, a SLJ Best Book of the Year, and a Junior Literary Guild Selection.
Document 6: The Spirit House: The Spirit House is a 1993 young adult novel by William Sleator. It was later followed up with the 1997 "Dangerous Wishes".
Document 7: World War I casualties: The total number of military and civilian casualties in World War I was about 40 million: estimates range from 15 to 19 million deaths and about 23 million wounded military personnel, ranking it among the deadliest conflicts in human history.
Document 8: World War II casualties: World War II was the deadliest military conflict in history in absolute terms of total casualties. Over 60 million people were killed, which was about 3% of the 1940 world population (est. 2.3 billion). The tables below give a detailed country - by - country count of human losses. World War II fatality statistics vary, with estimates of total deaths ranging from 50 million to more than 80 million. The higher figure of over 80 million includes deaths from war - related disease and famine. Civilians killed totalled 50 to 55 million, including 19 to 28 million from war - related disease and famine. Military deaths from all causes totalled 21 to 25 million, including deaths in captivity of about 5 million prisoners of war.
Document 9: World War I casualties: The total number of military and civilian casualties in World War I was more than 41 million: there were over 18 million deaths and 23 million wounded, ranking it among the deadliest conflicts in human history.
Document 10: United States military casualties of war: Rank War Years Deaths Deaths per day U.S. population in first year of war Deaths per population American Civil War 1861 -- 65 750,000 avg. (U.S. / Confederate) 520 31,443,000 2.385% (1860) World War II 1941 -- 45 405,399 297 133,402,000 0.307% (1940) World War I 1917 -- 18 116,516 279 103,268,000 0.110% (1920) Vietnam War 1961 -- 75 58,209 11 179,323,175 0.032% (1970) 5 Korean War 1950 -- 53 54,246 45 151,325,000 0.036% (1950) 6 American Revolutionary War 1775 -- 83 25,000 11 2,500,000 1.00% (1780) 7 War of 1812 1812 -- 15 15,000 15 8,000,000 0.207% (1810) 8 Mexican -- American War 1846 -- 48 13,283 29 21,406,000 0.057% (1850) 9 Iraq War 2003 -- 2011 4,497 294,043,000 0.002% (2010) 10 Philippine -- American War 1899 -- 1902 4,196 3.8 72,129,001 0.006% (1900) 11 Spanish -- American War 1898 2,246 8.9 62,022,250 (1890) 12 War in Afghanistan 2001 - present 2,216 0.36 294,043,000 (2010)
Document 11: The Boy Who Reversed Himself: The Boy Who Reversed Himself (1986) is a science fiction novel by William Sleator. The novel deals with an exploration into other dimensions, and provides a journey into the world beyond our own.
Document 12: World War II casualties: World War II was the deadliest military conflict in history in absolute terms of total casualties. Over 60 million people were killed, which was about 3% of the 1940 world population (est. 2.3 billion).
Document 13: Parasite Pig: Parasite Pig is a young adult science fiction novel written by William Sleator. It is the sequel to the 1984 book "Interstellar Pig".
Document 14: Marco's Millions: Marco's Millions (2001) is a science fiction novel by William Sleator. Marco and his sister Lilly need to deal with the stress that they are the only ones that can save the world. It is a prequel to the main book, "The Boxes".
Document 15: Nick Sagan: Nick Sagan (born September 16, 1970 in Boston, Massachusetts) is an American novelist and screenwriter. He is the author of the science fiction novels "Idlewild", "Edenborn", and "Everfree", and his screen credits include episodes of "" and "". He is the son of astronomer Carl Sagan and artist and writer Linda Salzman.
ground_truth: American Civil War
sub_queries: The Boy Who Reversed Himself >> author Answer: William Sleator
William Sleator >> country of citizenship Answer: America
in what war did America lose the most soldiers Answer: American Civil War