Obama didn’t actually do anything but get elected and said nice things. When he got the Peace Prize, people all over the world were confused and thought it was a joke.
> On May 6, with eight months left before he vacates the White House, Mr. Obama passed a somber, little-noticed milestone: He has now been at war longer than Mr. Bush, or any other American president.
It wasn't all inherited conflicts. He also oversaw the 2011 intervention in Libya, the 2014 involvement in Syria, and the 2014 re-intervention in Iraq after having withdrawn troops in 2011.
[1]: NYT: https://archive.is/diXo5
It's okay if a non-voting member of the Nobel org 'regrets' other peoples' decision because Obama didn't immediately withdraw from Iraq and Afghanistan and pardon Bin Laden. Maybe he can take some solace in the fact that he let Putin take Crimea and shoot down MH17, trading peace in 2014 for war in 2022.