The Brazilian Armed Forces acquired great political clout after the Paraguayan War. The politicization of the Armed Forces was evidenced by the Proclamation of the Republic, which overthrew the Empire, or within Tenentismo ("Lieutenants' movement") and the Revolution of 1930. Tensions escalated again in the 1950s, as important military circles (the "hard-line militars", old positivists whose origins could be traced back to the AIB and the Estado Novo) joined the elite, medium classes and right-wing activists in attempts to stop Presidents Juscelino Kubitschek and João Goulart from taking office, due to their supposed support for Communist ideology. While Kubitschek proved to be friendly to capitalist institutions, Goulart promised far-reaching reforms, expropriated business interests and promoted economical-political neutrality with the US.