“[My worst mistake was] probably failing to plan for the day after for what I think was the right thing to do in intervening in Libya,” Obama said on Fox News Sunday.

In 2011, the U.S. joined a multi-state coalition of European and Arab countries to intervene militarily in Libya. The intervention was meant to prevent Libyan strongman Muammar Gaddafi from carrying out attacks against civilians.

Hillary Clinton was the primary advocate for intervening and persuaded a reluctant presidential cabinet to support the effort.

Obama let the Europeans take the lead with military operations in what he termed as an American strategy of “leading from behind.” Ultimately Gaddafi was killed in October of 2011 and his regime overthrown.