Between 1962 and 1978 Blix was a member of the Swedish delegation at the Disarmament Conference in Geneva. He held several other positions in the Swedish administration between 1963 and 1976, and from 1961 to 1981 served on the Swedish delegation to the United Nations. From 1978 to 1979, Blix was the Swedish Foreign Minister.
Blix chaired the Swedish Liberal Party's campaign during the 1980 Referendurm on nuclear power, campaigning in favor of retention of the Swedish nuclear energy program.
Iraq was alternately praised and admonished by the IAEA for its cooperation and lack thereof. It was only after the first Gulf War that the full extent of Iraq's nuclear programs, which had switched from a plutonium based weapon design to a highly enriched uranium design after the destruction of Osiraq, became known.
and warned Iraq of "serious consequences" if it attempted to hinder or delay his mission
In his report to the UN Security Council on 14 February 2003, Blix claimed that "If Iraq had provided the necessary cooperation in 1991, the phase of disarmament -- under resolution 687 -- could have been short and a decade of sanctions could have been avoided." 
Blix's statements about the Iraq WMD program came to contradict the claims of the George W. Bush administration,
and attracted a great deal of criticism from supporters of the invasion of Iraq. In an interview on BBC TV on 8 February 2004, Dr. Blix accused the US and British governments of dramatising the threat of weapons of mass destruction in Iraq, in order to strengthen the case for the 2003 war against the regime of Saddam Hussein.
Newt Gingrich stated that approving Hans Blix as chief UN weapons inspector was one of the biggest mistakes the United States ever made.
In an interview with London's Guardian newspaper, Hans Blix said, "I have my detractors in Washington. There are bastards who spread things around, of course, who planted nasty things in the media" 
In 2004, Blix published a book, Disarming Iraq, where he gives his account of the events and inspections before the coalition began its invasion.
Ultimately, no stockpiles of weapons of mass destruction were found. 
Hans Blix said he suspected his home and office were bugged by the United States, while he led teams searching for Saddam Hussein's supposed weapons of mass destruction.Although these suspicions were never directly substantiated, evidence of bugging of UN security council representatives around the time the US was seeking approval from the council came to light after a British government translator leaked a document "allegedly from an American National Security Agency" requesting that British intelligence put wiretaps on delegates to the UN security council.

In December 2006, the Weapons of Mass Destruction Commission said in a report that Pakistan’s infamous and controversial nuclear proliferator Abdul Qadeer Khan could not have acted alone or “without the awareness of the Pakistani government”.
and Europe & USA: Behind the Scenes of a Political Rupture
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