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- United States — Defenses
United States — Defenses — Audiobooks
The Interest of America in Sea Power, Present and Future
by A. T. (Alfred Thayer) Mahan
America and the World War
by Theodore Roosevelt
Defenseless America
by Hudson Maxim
Straight America, a call to national service
by Frances Kellor
The United States and the War
by Gilbert Murray
The Invasion of America: a fact story based on the inexorable mathematics of war
by J. W. (Julius Washington) Muller
The Altar of Freedom
by Mary Roberts Rinehart
Our National Defense: The Patriotism of Peace
by George Hebard Maxwell