As president, he mostly followed the neoliberal economic policies that his predecessors from the PRI had adopted since the late 1980s. The first half of his administration saw a further shift of the Federal government to the right, strong relations with the United States and George W. Bush, unsuccessful attempts to apply a value-added tax to medicines and to build an airport in Texcoco, and a major diplomatic conflict with Cuban leader Fidel Castro. The murder of human rights lawyer Digna Ochoa in 2001 called into question the Fox administration's commitment to breaking with the authoritarian past of the PRI era.