The deposition of Rosas led to Argentina's present institutional framework, outlined in the 1853 constitution. The document, drafted by a legal scholar specializing in the interpretation of the United States Constitution put forth national social and economic development as its overriding principle. Where foreign policy was concerned, it specifically put emphasis on the need to encourage immigration and little else, save for the national defense against aggressions. This, of course, was forced into practice by Paraguayan dictator Francisco Solano López's disastrous 1865 invasion of northern Argentine territory, leading to an alliance between 1820s-era adversaries Argentina, Brazil and Uruguay and the loss of hundreds of thousands of lives (particularly Paraguay's own).