The US intervention in Libya was a key turning point for Putin in his attitude toward the US
The intervention was led by then-Secretary of State Hillary Clinton, who convinced President Barack Obama, wary of war with yet another Muslim country, to join a NATO-led coalition in ousting dictator Muammar Gaddafi.
At the time of the Libyan intervention, Putin was Russia's prime minister, and Dmitry Medvedev, widely considered Putin's protégé, was Russia's president with whom the Clinton-led State Department was attempting to "reset" relations. After Medvedev decided not to veto a US-backed UN Security Council resolution in favor of military intervention in Libya, Putin voiced his disagreement publicly, comparing the resolution to a "medieval call to the crusades."
Putin saw the move as "a case study in Western intervention: stir up protests, give them rhetorical support and diplomatic cover, and, if that doesn't work, send in the fighter jets," according to The New Yorker.
Several months later, Gaddafi was captured by Libyan rebels, dragged into the street, and killed. A video of the event circulated around the world while Libya collapsed into chaos.
In a now notorious reaction to news of Gaddafi's death, Clinton joked to a reporter, "We came, we saw, he died!"
Russian journalist Mikhail Zygar has written that Putin saw the takedown of Gaddafi, who had negotiated with the West at various points throughout his rule, as a lesson for Russia.
"When he was a pariah, no one touched him," Zygar wrote. "But as soon as he opened up he was not only overthrown but killed in the street like a mangy old cur."