In the sharpest, raunchiest attack anywhere in the media comedian Stephen Colbert launched the definitive takedown of Republican presidential candidate Donald Trump's big lie insisting that he has ended the so-called birther controversy about President Barack Obama — and that his rival Hillary Clinton started it.

Colbert stitched together an amazing string of video clips over the past five years featuring a blustery Trump touting his "serious" doubts that Obama was born in the US, backed up by nothing but inuendo — or fibs.

"I've been told that his birth certificate is missing ... that it doesn't exist," Trump tells CNN's Anderson Cooper in a 2011 clip. "Who told you?" Coopers asks.

Trump responds: "I just heard that two days ago from somebody."

He also claims that Obama's grandmother said he was born in Kenya.

In another snippet, Trump offers to pay $5m (£3.85m) to a charity if the president would release his college and passport records because "many, many people have questions and very serious questions" about the extensive long form Obama birth certificate (or "whatever it may be," says Trump) released by Hawaii.

Trump also tells CNN: "A lot of people don't agree with that birth certificate. A lot of people do not think it's authentic."

(He never forked over millions to a charity.)

The birther controversy is proving to have surprising negative staying power in the Trump campaign because it highlights a major party candidate doing something that has never been done in quite the same way in a presidential contest: brazenly insisting on a bald-faced lie that is simply known to be contrary to the facts. And there's a strong paper trail and video record that disproves Trump's liecreated by Trump himself.

As Colbert said, he knows Trump lied about the birther controversy, "because I am alive."

He added: "You don't get to flog this issue for five years and then act like you're correcting everybody else. We're not crazy. We were there. We all saw you do it. Even the people who support you saw you do it. It's why they support you."

The birther lie is popping up repeatedly in media and critics' discussions about "character" in a presidential candidate and in a president. Such a lie could have scuttled a campaign in the past, but that's not happening this time around.

"We're always used to spin," New York Times columnist David Brooks said on NPR. "But now we're in a reverse, Orwellian inversion of the truth with this. What's white is black, and what is up is down, what is down is up. And that really is something new in politics."