(CNSNews.com) - President Obama, asked to name his "worst mistake" as president, pointed to the intervention that toppled Libya's Moammar Gaddafi.
Libya is now a failed state where America's enemies are "metastasizing," to use Defense Secretary Ashton Carter's word.
In an interview with "Fox News Sunday," host Chris Wallace asked Obama to name his "greatest accomplishment" and his "worst mistake" as president.
Obama said his greatest accomplishment was "saving the economy from a great depression." And his worst mistake: "Probably failing to plan for the day after what I think was the right thing to do, in intervening in Libya."
In a speech to the nation on March 28, 2011, President Obama explained his decision to order military strikes in Libya (without congressional authorization) to stop dictator Gaddafi from killing his own people.
"Of course, there is no question that Libya -– and the world –- would be better off with Gaddafi out of power," Obama said at the time.
At a Pentagon briefing last week, Gen. David Rodriguez, commander of U.S. Africa Command, told reporters that Islamic State terrorists pose a "growing threat" in Libya.
Rodriguez said there are "around 4 (thousand) to 6,000" ISIS fighters now operating in Libya, a number that has about doubled in the past 12-18 months, based on intelligence estimates.
Some of those fighters came to Libya from other countries, and some are Libyans who have "pledged allegiance to ISIS."
A reporter asked Rodriguez if the Islamic State fighters in Libya have set a goal of attacking nearby Europe or the United States.
"Yeah, that's been their aspiration all the time, and they are continuing with the same threats that ISIS main is making, yes," Rodriguez responded.
He said the U.S. is "going after" ISIS fighters in Libya who pose an "imminent threat to U.S. personnel and facilities."
A reporter asked Rodriguez if the U.S. would be willing to act if the number of ISIS fighters in Libya doubles again in the next year or so.
"That's a decision for the national command authority and leadership," Rodriguez said. He called it a "possibility."
"The effort right now continues to remain on the imminent threats to U.S. personnel and facilities. We have all the authorities and resources we need to continue to do that, and we will continue to do that. And that's the number one concern for us right now.
"Now as the -- the question I think what you're asking is really is when that becomes overwhelming (the number of ISIS members in Libya), which it is not right now, then what do you do? And again, that will have to be a policy decision, if it gets to that point."
Rodriguez said it will be a "challenge" for the number of ISIS fighters in Libya to keep growing, given the Libyan people's attitude toward foreigners. Various militias are fighting ISIS, when those militias aren't fighting each other.
"But it's going to be a challenge for them to get to that point because of the Libyan population, people and militias that are out there. So we'll have to see how that develops. Is it possible? It is. But right now we're not -- I'm not concerned about that, OK."