Republican presidential candidate Donald Trump said Tuesday that although he believes the Iraq war was a mistake, he does not believe the war in Afghanistan falls into that same category -- apparently reversing his position on the war even as he continues to fault the George W. Bush administration's foreign policy.

"How can you say you were safe under his brother when we just had the worst attack in the history of our country?" Trump said on CNN Tuesday morning, echoing his controversial criticism of the Bush administration's national security record with regard to the Sept. 11, 2001, attacks.

"You can say, 'Yes, we did well after.' But we also made mistakes there.... We went into Iraq, which was a disaster decision, just a disastrous decision," Trump said. "Not Afghanistan, because that's probably where we should have gone in the first place."

The business mogul has sparked a national conversation about the Bush administration's legacy on national security and whether it successfully mitigated the war on terror. Although he has frequently criticized George W. Bush for invading Iraq, his recent comments holding him accountable for 9/11 represent an escalation of recriminations against the former president -- and, by extension, his brother Jeb Bush, a rival for the GOP presidential nomination.

Trump has notably gone on the record criticizing the war in Afghanistan, frequently talking about the two wars with similar disdain. When pressed on CNN about his previous denunciation of the decision to intervene in Afghanistan, Trump denied making such statements.

"I never said that. Okay, wouldn't matter, I never said it. Afghanistan is a different kettle. Afghanistan is next to Pakistan; it's an entry in. You have to be careful with the nuclear weapons," Trump said. "It's all about the nuclear weapons. By the way, without the nukes, it's a whole different ballgame."

Trump has aggressively gone after the Bush administration at the same time that he wages battle against Jeb Bush, who has defended his brother’s record on foreign policy by saying that Trump’s statements show a “lack of seriousness.” That disagreement has been politically fraught and has exposed deep divisions among Republican voters.

Among Trump’s objections is that the FBI, the CIA and the National Security Council were not communicating with each other or with the White House effectively.

"Say what you want, but then we went out and we attacked the wrong country because we went out and attacked Iraq. They had no weapons of mass destruction, as you know ... and as we found out in spades," he said. "We destabilized the entire Middle East. The Middle East is a mess right now because of Iraq."