The Chaco War began on 18 July 1932, when Salamanca announced to the startled nation that the Paraguayan forces had seized a Bolivian fort in the Chaco. That this fort was in reality a Paraguayan one that had been seized by the Bolivians at the end of May was ignored. Salamanca ordered a major offensive that night and carried out a state of siege. At this point, the Bolivian General Staff refused to endorse Salamanca's war plans. It claimed that the army was unprepared for a major assault, and considered the escalation of the conflict to be out of all proportion to the incident. So intense was the debate between the general staff and the president that Salamanca was finally forced to acknowledge full responsibility for all his decisions relating to the initiation of the conflict in a formal written document. Having thus absolved itself from any responsibility for the assault and subsequent actions, the general staff declared these actions were against the national interests, but agreed to carry out Salamanca's decisions.

Despite Paraguayan and international protests of the legitimacy of Bolivian claims, local leaders supported Bolivia's position and attacked Paraguay as the initiator of the bellicose situation. Manifestos of nationalist support were signed by everyone from Alcides Arguedas on the right to Franz Tamayo and Carlos Montenegro on the left. There were also major patriotic demonstrations in all the urban centers as the economic crisis was momentarily forgotten.