At the invitation of the United States government, the Organization for Security and Cooperation in Europe (OSCE) sent a team of observers to monitor the presidential elections in 2004. It was the first time the OSCE had sent observers to a U.S. presidential election, although they had been invited in the past. In September 2004 the OSCE issued a report on U.S. electoral processes and the election final report. The report reads: "The November 2, 2004 elections in the United States mostly met the OSCE commitments included in the 1990 Copenhagen Document. They were conducted in an environment that reflects a long-standing democratic tradition, including institutions governed by the rule of law, free and generally professional media, and a civil society intensively engaged in the election process. There was exceptional public interest in the two leading presidential candidates and the issues raised by their respective campaigns, as well as in the election process itself."

Answer this question, if possible (if impossible, reply "unanswerable"): Why did OSCE come to the US in 1990?
unanswerable