Then-Secretary of State Hillary Clinton at a March 2011 international conference on the Libya crisis in London. (AP Photo, File)

(CNSNews.com) – In an email to then-Secretary of State Hillary Clinton shortly after the U.N. Security Council in March 2011 authorized military intervention in Libya, a former senior State Department official praised her achievement in “turning POTUS around on this.”

In her reply, Clinton expressed hope “for a soft landing for everyone’s sake.”

The message to Clinton, among the latest batch of her private server emails released by the State Department at the weekend, came from Anne-Marie Slaughter, who the previous month had returned to a politics professorship at Princeton University after serving as Clinton’s director of policy planning.

“I cannot imagine how exhausted you must be after this week, but I have NEVER been prouder of having worked for you,” Slaughter wrote in the March 19 email, which carried the subject line “bravo!”

“Turning POTUS around on this is a major win for everything we have worked for,” Slaughter added.

Replying, Clinton wrote, “Keep your fingers crossed and pray for a soft landing for everyone’s sake.”

Slaughter was an ardent support of intervention in Libya, where Muammar Gaddafi early that year launched the bloodiest crackdown on dissent in his 41-year rule. Her message to Clinton reinforces the view that Clinton persuaded a reluctant President Obama to shift direction on Libya.

On the night of March 17, the Security Council had passed a resolution authorizing a no-fly zone and “all necessary measures” short of foreign occupation to protect civilians from Gaddafi’s forces.

Acting under that resolution, U.S., British and French forces launched airstrikes on Libyan regime targets on March 19, an operation that came under NATO military command several days later.

By October, Gaddafi was dead – killed by rebel militiamen – and Libya quickly spiraled into chaos that largely continues to the present day, with rival government vying for control and the Islamic State of Iraq and Syria (ISIS), al-Qaeda and other jihadist groups active. A Sept. 11, 2012 terrorist attack in Benghazi cost the lives of lives of the U.S. ambassador, a foreign service officer and two Navy Seals.

The wisdom of the U.S. intervention in Libya, and the role played by Clinton, continues to generate debate at a time when the former secretary of state is contesting the Democratic Party nomination for the presidency.

During one of many congressional hearings on the Benghazi attack, Clinton was asked by Rep. Peter Roskam (R-Ill.) last October about the role she played in the decision to take military action in Libya in March 2011.

“There were senior voices within the White House that were opposed to military action – Vice President [Joe] Biden, Department of Defense, [Defense] Secretary [Bob] Gates, the National Security Council and so forth,” Roskam said. “But you persuaded President Obama to intervene militarily. Isn’t that right?”

Clinton said there were “many in the State Department” who believed intervention to protect the Libyan people was in America’s interests, but that amid varying opinions,

“at the end of the day, this was the president’s decision.”

In a New York Times op-ed days before the Security Council Libya vote, Slaughter made a case for military intervention, listing five arguments that were coming at the time from anti-intervention voices and then dismissing each one.

Challenging the line of reasoning that intervention was not in the U.S. interest, she wrote that “we have a chance to support a real new beginning in the Muslim world – a new beginning of accountable governments that can provide services and opportunities for their citizens in ways that could dramatically decrease support for terrorist groups and violent extremism.”

Confronting the argument that the U.S. did not know what a post-Gaddafi Libya would look like, Slaughter acknowledged that the U.S. “should not expect a rosy, Jeffersonian Libya.”

“But the choice is between uncertainty and the certainty that if Colonel Qaddafi wins, regimes across the region will conclude that force is the way to answer protests,” she said.

“And when Colonel Qaddafi massacres the opposition, young protesters across the Middle East will conclude that when we were asked to support their cause with more than words, we blinked,” Slaughter continued. “Americans in turn will read the words of Mr. Obama’s June 2009 speech in Cairo, with its lofty promises to stand for universal human rights, and cringe.”