But the interview was some 17 months after the war began.
Trump also said that if he had been in Congress at the time, he would have voted against the resolution allowing for the use of force in Iraq - but that was voted on in October of 2002, well before some of his statements that raised questions about the war.
What's more - only 6 Republicans in the House voted against that resolution, which was seen as a test of support for President George W. Bush at the time.
Trump's back-and-forth on Iraq has certainly been noticed in the news media, as various reports on his Ohio remarks weighed in with what he has said in the past.
"Trump Insists, Falsely, that He Opposed Iraq War," the Associated Press headlined.
"Trump tries to prove he was against the Iraq War," said Politico.
"Trump tries to convince public that he opposed Iraq War," reported CNN.
Why is the Iraq War a big deal? It's because Trump wants to show that he was on the other side from Hillary Clinton - as Trump argues she is "trigger-happy" - more than ready to send U.S. troops into a war - in this case a war that Trump says he opposed.