At the root of the Obama team and liberal punditocracy’s meltdown over vice-presidential nominee Paul Ryan’s speech at the Republican National Convention are two problems, largely of Obama’s making. Both will be front and center for the rest of the campaign.

The first, aptly, described by Ben Smith, is the decision to convert policy arguments into factual disputes and label Republicans as “liars.” It is endemic in this campaign. As Smith put it: “The Democrats are hoping to do to Paul Ryan what Republicans so successfully did to Al Gore: To conflate stray real personal exaggerations; rhetorical simplifications; and actual policy differences into an unfair character attack. Ryan (and now Romney) is in fact far more honest than any Republican national figure in memory in his explicit plan to turn Medicare into a less-expensive voucher system and to cut health care spending for poor people deeply. That had been Democrats first, and obvious, point of attack, and is an utterly valid one. Also: Romney and Ryan want to repeal a vast program of expanded health coverage. Obama wants to implement it.”

With regard to the Janesville, Wis., plant, the “He Lied!” set was largely left holding an empty bag when it turned out that Ryan’s actual comments were accurate. (“It’s hard to see the outrageous lie in this complicated story. And indeed, an aggressive fact checker might also raise an eyebrow at Obama’s original comment that appropriate government help could keep the plant open another century.”)

Wisconsin Gov. Scott Walker sums up the emptiness of the Ryan critics’ hyperventilation:

So why is the Obama campaign so upset? Like so many things in this election, they don’t want to focus on how Obama’s promises have turned out. They want to blame somebody else for our problems. They are telling us the plant closed before Obama could put his policies in place. So we shouldn’t blame him for that.

But here’s where the Obama campaign’s argument goes off the rails — and here’s why Ryan’s speech scares them so much.

Ryan wasn’t blaming Obama for closing that Wisconsin plant. As he said in his speech. “President Barack Obama came to office during an economic crisis, as he has reminded us a time or two.” Ryan said, “Those were very tough days, and any fair measure of his record has to take that into account.”

This election is not about what happened before Obama become president. It’s about his failure to make things better, and it is about where we are going in the future.

Obama didn’t close that factory — but he hasn’t re-opened it either. Despite telling the people of Janesville that was the plan. When GM announced in October 2008 that it would be halting production there, then-candidate Obama said, “As president, I will lead an effort to retool plants like the GM facility in Janesville so we can build the fuel-efficient cars of tomorrow and create good-paying jobs in Wisconsin and all across America.” . . .

The president has not brought prosperity back to Janesville.

“And that’s how it is in so many towns today,” Ryan said, “where the recovery that was promised is nowhere in sight.”

That’s a fact that no amount of spin or hysteria can change. And it’s a fact that seems to terrify the Obama campaign to its very core.

At the end of these arguments Obama and his spinners have convinced virtually no one who didn’t previously agree with them of the Republicans’ mendacity. Calling the other side “liars” doesn’t persuade voters to join your cause.

And this brings up to the second, even more critical dilemma, which is the president’s overpromising problem. Romney signaled that he’ll highlight the gap between promises and performance when the GOP nominee mocked the president’s grandiose ambitions. (“President Obama promised to begin to slow the rise of the oceans. And to heal the planet. My promise is to help you and your family.”)

It sometimes has seemed that the more Obama had repeated a promise the less likely it was to be kept. He was going to go “line by line” through the budget. He was going to put aside blame and hyper-partisanship. Now these promises sound like nails on the chalkboard to the voters, reminders of how far short of expectations he has fallen.

His 2008 acceptance speech is going to be a gold mine for the Republicans:

We measure progress by how many people can find a job that pays the mortgage, whether you can put a little extra money away at the end of each month so you can someday watch your child receive her college diploma.

We measure progress in the 23 million new jobs that were created when Bill Clinton was president when the average American family saw its income go up $7,500 instead of go down $2,000, like it has under George Bush.

It’s gone down about $4,000 under Obama. And we’ve got 8.3 percent unemployment.

Let’s recall what else Obama promised: “Change means a tax code that doesn’t reward the lobbyists who wrote it, but the American workers and small businesses who deserve it.” He has never promised a tax reform plan to achieve this.

Then there was the health-care reform promise that wound up bearing little resemblance to Obamacare: “If you have health care — if you have health care, my plan will lower your premiums. If you don’t, you’ll be able to get the same kind of coverage that members of Congress give themselves.”

On foreign policy the gap between promise and achievement was even greater: “I will rebuild our military to meet future conflicts, but I will also renew the tough, direct diplomacy that can prevent Iran from obtaining nuclear weapons and curb Russian aggression.” We are now sitting on the eve of sequestration (after $78 billion has already been cut from defense). Iran is closer than ever to getting the bomb. And Russian international aggression and domestic oppression have increased.

His high-minded sentiments now ring as hollow as as those styrofoam columns in Denver. He pronounced that “one of the things that we have to change in our politics is the idea that people cannot disagree without challenging each other’s character and each other’s patriotism.” But of course it is this declaration like no other that now comes back to haunt him: “ If you don’t have a record to run on, then you paint your opponent as someone people should run from. You make a big election about small things.”

Obama, as he returns to his party’s convention, will not only be measured against his opponent but against Obama 2008. Very little of what Obama promised in 2008 has come to fruition, and so much of what he railed against has become standard operating procedure. You wonder if Romney wouldn’t be smart to run comparative ads — Obama 2008 vs. Obama 2012. The current version would do very poorly.