in the early 1980s, tension in the american–brazilian relations centered on economic questions. retaliation for unfair trade practices loomed on the horizon and threatened brazilian exports of steel, orange juice, commuter aircraft, shoes and textiles. when president sarney took office in 1985, political issues, such as brazil's arms exports to libya and iran, again surfaced. brazil's foreign debt moratorium and its refusal to sign the non-proliferation treaty caused the united states to put brazil on its mandated blacklist, thereby restricting brazil's access to certain u.s. technologies.