In 1932, he fought against Bolivian forces in the Battle of Boquerón during the Chaco War. After the war he rose steadily in rank; by 1940, he had risen to the rank of major and joined the general staff in 1946. When the Paraguayan Civil War broke out in 1947, he commanded the artillery division at Paraguarí that ensured that President Higinio Morínigo won the war by destroying a working-class rebel area of Asunción. President Morínigo found Stroessner's military skills very useful and promoted him rapidly. As one of the few officers who had remained loyal to Morínigo, Stroessner became a formidable political and social player once he entered the higher echelons of the Paraguayan armed forces. He became a brigadier — and the youngest general officer in South America — in 1948. His accurate political sense failed him only once, when he found himself in 1948 on the wrong side of a failed coup attempt and had to be driven to the Brazilian embassy in the trunk of a car, earning him the nickname of "Colonel Trunk". Stroessner backed Felipe Molas López in a successful coup against Juan Natalicio González. He then backed Federico Chávez against Molas López and by 1951 he was Commander-in-chief of the Armed forces of Paraguay.