If you're talking about the bombing of Libya. There was no congressional approval and he didn't have to under the War Powers Act. I don't like it whether Obama or Trump uses it. I think it goes against the original intent of the constitution and leads to an imperial presidency.
https://www.theatlantic.com/politics/archive/2012/09/how-obama-ignored-congress-and-misled-america-on-war-in-libya/262299/
Obama had UN approval, France rightly lead the way.
And this Two days after the U.N. acted, the United States and other NATO countries, including Britain and France, enforced a no-fly zone over Libya by Gadhafi’s air force while starting to bomb his assets. Seven months later, in October 2011, after a military offensive backed by a group of Western powers, rebel forces conquered the North African country, located Gadhafi and killed him.
According to Alan J. Kuperman, writing in the March-April 2015 issue of Foreign Affairs: “Not only did Gadhafi endanger the momentum of the nascent Arab Spring, which had recently swept away authoritarian regimes in Tunisia and Egypt, but he also was poised to commit a bloodbath in the Libyan city where the uprising had started.”
Obama declared: “We knew that if we waited one more day, Benghazi—a city nearly the size of Charlotte—could suffer a massacre that would have reverberated across the region and stained the conscience of the world.” In the Rose Garden speech after Gadhafi’s death, Obama noted, “Without putting a single U.S. service member on the ground, we achieved our objectives.”