Jeane Kirkpatrick, Requiescat in pace.

A great lady and a great American has left us.

Jeane J. Kirkpatrick, an unabashed apostle of Reagan era conservatism and the first woman U.S. ambassador to the
United Nations, has died.

The death of the 80-year-old Kirkpatrick, who began her public life as a Hubert Humphrey Democrat, was announced Friday at the senior staff meeting of the U.S. mission to the United Nations.

Spokesman Richard Grenell said that Ambassador John Bolton asked for a moment of silence. An announcement of her death also was posted on the Web site of the American Enterprise Institute, a conservative-oriented think tank here where she was a senior fellow.

Kirkpatrick's assistant, Andrea Harrington, said that she died in her sleep at home in Bethesda, Md. late Thursday. The cause of death was not immediately known.

Kirkpatrick's health had been in decline recently, Harrington said, adding that she was "basically confined to her house," going to work about once a week "and then less and less."

Senate Majority Leader Bill Frist, R-Tenn., said that Kirkpatrick, who had a reputation as a blunt and acerbic advocate, "stood up for the interests of America while at the U.N., lent a powerful moral voice to the Reagan foreign policy and has been a source of wise counsel to our nation since leaving the government two decades ago. She will be greatly missed."

Karlyn H. Bowman, a colleague of Kirkpatrick's at AEI, called her "always insightful. Always interesting. Very thoughtful about modern American politics and foreign policy. A wonderful colleague."

Bowman also said that Kirkpatrick, who had been elevated to the U.N. post by President Reagan in 1981, had "served with great distinction" at the U.N. "She was a great patriot, a champion of freedom and we will certainly miss her at AEI and the country."

Kirkpatrick was known as a blunt and sometimes acerbic advocate for her causes. She remained involved in public issues even though she'd left government service two decades ago. She joined seven other former U.N. ambassadors in 2005 in writing a letter to Congress telling lawmakers that their plan to withhold dues to force reform at the world body was misguided and would "create resentment, build animosity and actually strengthen opponents of reform."

Bill Bennett, a former secretary of education under Reagan, the nation's drug czar under the first President Bush and a leading conservative opinion-maker, called her "very forceful, very strong, a daughter of Oklahoma, great sense of humor. She held her own."

Bennett said the Iraq Study Group so prominently in the news "would have been better with Jeane Kirkpatrick on it ... She had no patience with tyrannies, said they had to be confronted, you couldn't deal with tyrannies, that there were some people you could work with — these people you couldn't." (Thanks to AP for this obituary.)