Reykjavík Summit continued, and U.S.–Soviet relations – already strained by the failure of the Geneva Summit the previous year – were further strained by the Daniloff–Zakharov espionage affair. At Reykjavík, Reagan sought to include discussion of human rights, emigration of Soviet Jews and dissidents, and the Soviet invasion of Afghanistan. Gorbachev sought to limit the talks solely to arms control. The Soviets acceded to the "double-zero" proposal for eliminating INF weapons from Europe, as initially proposed by President Reagan in November 1981 (INF denoting "Intermediate-Range Nuclear Forces" as distinct from ICBMs, or intercontinental ballistic missiles). The Soviets also proposed to eliminate 50%
Nancy Reagan failed to include some $3 million worth of fashion items between 1983 and 1988 on their tax returns; they were billed for a large amount of back taxes and interest, which was subsequently paid. After President Reagan revealed that he had been diagnosed with Alzheimer's disease in 1994, she made herself his primary caregiver, and became actively involved with the National Alzheimer's Association and its affiliate, the Ronald and Nancy Reagan Research Institute in Chicago, Illinois. In April 1997, Nancy Reagan joined President Bill Clinton and former Presidents Ford and Bush in signing the Summit Declaration of Commitment in advocating