Complex sentence: Relations were strong under conservative neoliberal governments in Venezuela like that of Rafael Caldera, however, aggression by U.S. administrations increased after the socialist President Hugo Chávez assumed elected office in 1999.
Split into simpler sentences: Relations were strong under conservative neoliberal governments in Venezuela like that of Rafael Caldera. However, aggression by U.S. administrations increased after the socialist President Hugo Chávez assumed elected office in 1999.