Diplomatic history History International relations Mexican Americans Relations Revolutions Social aspects Subversive activities Archaeologists Commerce Espionage, American Espionage, German Foreign relations Insurrections -- Texas -- History -- 20th century Mexican Americans -- Texas -- History -- 20th century Mexico -- History -- Revolution -- 1910-1920 -- Diplomatic history Mexico -- History -- Revolution, 1910-1920 -- Social aspects Military intelligence Plan de San Diego Smuggling Subversive activities -- Texas -- History -- 20th century Texas -- Relations -- Mexico World War, 1914-1918