On June 3, 2008, Sen. Barack Obama clinched enough delegates to win the Democratic nomination for president of the United States.

On June 3, 2008, General Motors CEO Rick Wagoner announced that, because of shifting consumer purchases, four GM auto plants would close by 2010 or “sooner if demand dictates.” On his list was the SUV plant in Janesville, Wis.

On June 3, 2008, Rep. Paul Ryan (R-Wis.) said about that plant closure: “Growing up and living in Janesville, this is something we’ve always feared.” The workers at Janesville expected this as early as December 2007. GM had announced a production cutback, and by spring was offering employees buyouts.

On June 3, 2008, Obama, who had visited the plant earlier in the year, released this statement: “Today’s news is a painful reminder not only of the challenges America faces in our global economy, but of George Bush’s failed economic policies.” He then proposed that we fund the automakers to retool their factories for the fuel-efficient cars that America was starting to purchase.

For Janesville though, Obama entered the White House too late.

Ryan certainly knows the actual history of the GM plant in Janesville.

More than four years later, on Aug. 16, campaigning as the VP pick of the party that would have let GM be liquidated, Ryan told a crowd, “one of the reasons that plant got shut down was $4 gasoline. You see, this costs jobs. The president’s terrible energy policies are costing us jobs.”

That was a lie. Ryan knows this. Obama’s energy policies had nothing to do with the price of gas in 2008.

It didn’t matter.

On Aug. 29, as Ryan accepted the nomination for vice president, he knowingly lied again to the entire nation:

“My home state voted for President Obama. When he talked about change, many people liked the sound of it, especially in Janesville, where we were about to lose a major factory… Right there at that plant, candidate Obama said: ‘I believe that if our government is there to support you … this plant will be here for another hundred years’… Well, as it turned out, that plant didn’t last another year. It is locked up and empty to this day.”

Candidate Obama was right. Eventually he saved that entire company and more than 1 million auto jobs. But he could not reverse a corporate decision made well before he took office.

Ryan knows this.

But for Ryan and the Romney campaign, the truth doesn’t matter. Their campaign pollster admitted it: “We’re not going to let our campaign be dictated by fact-checkers,” Neil Newhouse said this week.

That’s painfully obvious. Fact-checkers should take the weekend off after going through Ryan’s lie-larded speech on Wednesday. Factcheck.org; Politifact; Glenn Kessler from The Washington Post — all must be exhausted from labeling as untrue the lies flowing from Ryan’s mouth. Like a river.

From the “we built it” quote that was deliberately taken out of context, to the continuing lie about welfare and spending, to the speeches from many candidates that contained some variation of all the above — this entire GOP convention has been one continuous lie.

But the display by Ryan is one for the record books.

The “we built it” theme lie. The Medicare lie. The Simpson-Bowles lie. The credit-rating downgrade lie. The Janesville lie. Not to mention the “misleading” statements such as the Republicans would “protect the weak,” when 62 percent of Ryan’s budget cuts target poor families. Or that health care, not the economy, was the president’s first order of business when the stimulus was first passed. Others have catalogued the lies ad nauseum.

My question is: Are the American people going to give Ryan’s serial lying a pass? Is it OK to voters that the GOP vice presidential nominee delivered the speech well but his content was pure poison? Have we become so immune to lies that it’s the new normal?

Please tell me no.

“We will not duck the tough issues, we will lead,” Ryan promised last night. He mentioned leading and leadership eight times in his speech. But he’d better bone up on what leadership is all about. More than anything, “leadership” is about honesty.

The No. 1 quality people look for in leaders, James Kouzes and Barry Posner state in their iconic book, “The Leadership Challenge,” in which they cite more than 40 years of extensive surveys across six continents, is honesty. People want to trust that their leaders will do what they say they will do. Of course we want to believe we will not be duped. Of course we want to be led honestly.

I couldn’t help thinking lastnight, we have been sold a bill of goods by a slick-haired, earnest-looking, fast-talking salesman. Harold Hill, move over. Apologies to Meredith Wilson of “The Music Man” fame, but if these guys win — we surely got trouble, my friends. Trouble with a capital “T” and that rhymes with “P” and that stands for “Paul.”

Jennifer Granholm is the former governor of Michigan, serving from 2003 to 2011. She is now host of “The War Room” on Current TV. She is also a visiting public policy and law professor at the University of California, Berkeley. Follow her on Twitter @JenGranholm.

Jennifer Granholm is the former governor of Michigan, serving from 2003 to 2011. She is now host of “The War Room” on Current TV. She is also a visiting public policy and law professor at the University of California, Berkeley. Follow her on Twitter @JenGranholm.