Republican presidential candidate Mitt Romney insisted on Wednesday that President George W. Bush would never have invaded Iraq if he had known that were no weapons of mass destruction (WMD) in the country.

"If we knew at the time of our entry into Iraq that there were no weapons of mass destruction, if somehow we had been given that information, why, obviously we would not have gone in," the candidate told MSNBC's Chuck Todd.

"You don't think we would have gone in at all?" Todd asked.

"Well, of course not," Romney declared. "The president went in based upon intelligence they had weapons of mass destruction. Had he known that was not the case, the U.N. would not have put forward resolutions authorizing this type of action. The president would not have been pursuing that course, but we did not know that. Based upon what we knew at the time, we were very much under the impression as a nation -- as our president was under the impression -- that they had weapons of mass destruction, that Saddam Hussein was intent on potentially using those weapons. And so, he took action based upon what he knew."

"But to go back and say, 'Knowing what we know now, would we have gone in?' Well, knowing what we know now, they did not have weapons of mass destruction. There would have been no effort on the part of our president or others to take military action," the former Massachusetts governor added.

There is evidence to suggest that Bush was told that Iraq had no WMD before he gave the order to launch a military action that would eventually last longer than World War II and cost more than the Vietnam War.

Two former senior CIA officers revealed to Salon that prior to the invasion, then-CIA director George Tenet briefed Bush on intelligence that Hussein had no WMD, but the president chose to keep the intelligence secret.

Author Ron Suskind reported that Bush was also informed in early 2003 that Iraq did not have weapons of mass destruction.

The Sunday Times revealed in 2005 that top-secret British documents showed "the intelligence and facts were being fixed around the policy" by the Bush administration before the war began.

Mickey Herskowitz, who was hired in 1999 to help Bush construct an autobiography, said that the then-Texas governor had talked about invading Iraq even before taking the presidential oath.

"I'll tell you, he was thinking about invading Iraq in 1999," Herskowitz told freelance journalist Russ Baker. "One of the things he said to me, is 'One of the keys to being seen as a great leader is to be seen as a commander-in-chief.' And he said, 'My father had all this political capital built up when he drove the Iraqis out of (Kuwait) and he wasted it."

"He said, 'If I have a chance to invade Iraq, if I had that much capital, I'm not going to waste it. I'm going to get everything passed I want to get passed and I'm going to have a successful presidency.'"

Watch this video from MSNBC's The Daily Rundown, broadcast Dec. 21, 2011.