Flournoy told The Washington Post, "In some cases, preemptive strikes against an adversary's [weapons of mass destruction] capabilities may be the best or only option we have to avert a catastrophic attack against the United States.

[19] In 2009, as under secretary of defense for policy, she also supported a US "civilian surge" in Afghanistan, coupling increased economic aid with at least 400 new counter-insurgency experts, and doubling the US military presence to 68,000 troops by the end of the year.

[2] On December 12, 2011, Flournoy announced that she would step down in February 2012 to return to private life and contribute to President Barack Obama's re-election bid.

[21] In 2011, Flournoy, then under secretary of defense for policy, helped persuade President Obama to intervene militarily in Libya,[22][23][24] despite opposition from members of Congress and key White House advisors, such as Joe Biden, Vice President; Tom Donilon, National Security Advisor; and Robert Gates, Defense Secretary.

[23] Flournoy supported the NATO-led imposition of a no-fly zone over Libya to oust resistant leader Muammar Gaddafi, accused of ordering the killing of demonstrators and promising to "hunt the rebels down and show no mercy.

[25] After leaving the Obama administration, Flournoy joined Boston Consulting Group as a senior advisor[26] to its Washington D.C.–based public sector practice.

[24] Critics who disagreed with Flournoy described the war on Libya as "disastrous" in its destabilization of entire regions in the Middle East and North Africa,[11] facilitating the transfer of arms to extremists across countries.

Two years after the ouster of Muammar Gaddafi, Flournoy defended the US military intervention in Libya, telling the Council on Foreign Relations: "I think we were right to do it.

[31] In June 2016 while she was rumoured to be "Hillary Clinton's Likely Defense Secretary", Flournoy advocated regime change in Syria, supporting "limited military coercion" to remove President Bashar al-Assad from office.

[32] In 2017, Flournoy, along with Antony Blinken, US Deputy Secretary of State in the Obama administration, co-founded WestExec Advisors, a consulting firm, where she holds the post of managing partner.

She has received some criticism for her role as a director at Booz Allen Hamilton, including by authors affiliated with the Project on Government Oversight (POGO).

"I would hate to see some in Congress decided they are going to hold hostage our security assistance to Israel as a way of protesting their policies in the West Bank.

[45] During the 2020 US presidential election, Flournoy stated that she opposed lifting economic sanctions against North Korea and Iran, though might support waivers for medical supplies during the global COVID-19 pandemic.

[47] In an August 2020 interview with Defense News, Flournoy stated that she favored shifting money from more traditional military expenditures to unmanned systems "that dramatically improve .

[48] In November 2020, when Flournoy was under consideration for Secretary of Defense, she wrote, “the department and Congress may want to consider a new type of funding authority that supports both the development and testing of new digital technologies."

[49] In June 2020 Flournoy argued that the US must invest in new military technologies and more long-range missiles, escalate US troop deployment to the South China Sea area, and step up roving war games in Asia to deter Chinese aggression.

[50][51] Without such ramped-up US military activity and absent the technology to ward off a Chinese cyber attack on US navigation systems, Flournoy asserted the US could stumble into a nuclear confrontation with China over Taiwan sovereignty.