(CNN) - The ongoing spat between Republican frontrunners Mitt Romney and Newt Gingrich plodded on Wednesday as Romney accused his rival of economic ignorance.
Romney was responding to a call from Gingrich to return the money he made at Bain Capital, a private equity firm he helped found in the 1980s. On Monday Gingrich said Romney and his company were responsible for "bankrupting companies and laying off employees."
"Unfortunately the speaker's way off on that," Romney said Wednesday on Fox News. "In my enterprise, we had the occasion to help build tens of thousands of jobs, and he doesn't understand the economy if he doesn't understand that sometimes businesses succeed and sometimes fail."
Romney quarreled with Gingrich's suggestion that his former profession was bad for the country.
"To suggest that there's something un-American or something wrong about investing in an enterprise that ultimately doesn't succeed bespeaks an extraordinary lack of understanding about how the economy works," Romney said.
Romney also brought up a point his campaign began pounding early Wednesday: comments Gingrich made in 2008 that called on anyone who profited from Fannie Mae and Freddie Mac to return the money.
Romney's campaign released a video of Gingrich discussing the mortgage giants' failures, saying: "Everybody who was profiting from them should pay the cost of having failed. And the general taxpayer should not bear that burden."
On Fox, Romney followed up his request for Gingrich to return the money he made consulting for the mortgage giant.
"He said anyone who profited from Freddie Mac should give the money back. Well, he profited $1.6 million from an agency that helped bring down the entire economy; he ought to give it back," Romney said.
Romney also went after President Barack Obama for his handling of a downed American drone in Iran, using his harshest language yet to criticize Obama for not doing more to prevent sensitive information from getting into Iranian hands.
"He was extraordinarily weak and timid in a critical moment," Romney said. "This will have severe implications for us, long term, and it was a terrible mistake on his part. I find it incomprehensible that he didn't destroy it, or go get it. I think destroying it would have been a good deal easier. Destroy it immediately, or go get it."
On Monday, Obama said the U.S. had asked Iran to return the drone, but on Tuesday, Iranian President Mahmoud Ahmadinejad said on an Iranian television station that his country "has been able to control" the downed RQ-170 Sentinel drone.
U.S. officials have not confirmed whether or not video released last week by Iranian state media indeed shows the downed drone, and have not commented on the capacity of the drone to self destruct.
Romney said that Obama was making a mistake in not at least attempting to recover the aircraft.
"The idea of letting it fall into the hands of people who will use it against us, use the intelligence capacity against us, is an extremely enormous mistake on the part of this president," Romney said.