After years of being criticised for exploiting the September 11 terrorist attacks for political gain, former New York mayor Rudi Giuliani has stunned the world by appearing to forget the deadliest international terrorist attack in history.
Speaking at a rally for Donald Trump in Ohio on Monday, Giuliani said: "Under those eight years, before Obama came along, we didn't have any successful radical Islamic terrorist attack inside the United States. They all started when Clinton and Obama came into office."
Giuliani was the mayor of New York City during the September 11 attacks. His handling of the tragic event formed much of the basis of his short-lived bid for the office of president in 2007-08.
So heavily did Giuliani's campaign lean on his 9/11 credentials that during the presidential debate, then-Senator Joe Biden quipped, "Rudi Giuliani. There's only three things he mentions in a sentence: a noun, a verb and 9/11."
Social media users have reacted with a mixture of incredulity and outrage, accusing the lawyer and businessman of forgetting the very incident at the heart of the "Never forget" slogan that became ubiquitous after the attacks.
Rudi Giuliani forgetting about 9/11 is the 9/11 of never forgetting.— Erin Gloria Ryan (@morninggloria) August 15, 2016
The remarks are even more bizarre in light of Giuliani's preceding comments, which directly reference 9/11 as an Islamic terrorist attack.
Introducing Trump's running mate Mike Pence to the crowd, Giuliani said Pence was a member of the Foreign Affairs and Judiciary committees "during the time of September 11th, when we went through the worst foreign attack in our history since the War of 1812".
"Remember, we didn't start this war. They did. We don't want this war. They do. And they didn't start it even in 2001. They attacked the World Trade Centre in 1993," Giuliani said.
"And they attacked it under the ideology of radical Islamic extremism."
It is not the first occasion Giuliani has apparently failed to remember or wilfully omitted the event that arguably came to define his public career.
In 2010, on US morning talk show Good Morning America, Giuliani claimed: "What he [Obama] should be doing is following the right things that Bush did. One of the right things he did was treat this as a war on terror. We had no domestic attacks under Bush."
George W Bush was president during the September 11 attacks.