(Revised and updated @ 5:55 pm ET)

In an attack likely to conjure up for many President Reagan's successful use of Cadillac-driving welfare queens as an issue in presidential politics, Mitt Romney's campaign accused President Obama of using his power to weaken work requirements for welfare recipients.

No sooner did the Romney campaign unleash its attack than the Obama campaign counterattacked, accusing Romney's operation of willfully distorting the truth.

While it gets somewhat complicated, here's an attempt to explain what all the fuss is about.

Romney's latest attack springboards off a July 12 Health and Human Services Department memo. The memo informed states that, under certain circumstances, the Obama administration would waive certain work requirements of the welfare overhaul law if states could show that the added flexibility would allow them to move welfare recipients to work more effectively.

Republican governors — including Romney, when he was governor of Massachusetts — have long sought such flexibility, but to no avail. They say the flexibility would give states latitude to try new approaches.

When the Obama administration announced its willingness to issue waivers, criticism from Republicans quickly followed.

Writing for the liberal publication The Nation, Greg Kaufmann provides background on how the flexibility is supposed to work. A fact sheet from the conservative Heritage Foundation titled "Gutting Welfare Reform: Ending Welfare as We Know It" provides Republican objections to Obama's action.

Those objections are embedded in a new Romney campaign TV ad. In a conference call with reporters Tuesday, Ed Gillespie, a GOP big gun and top adviser to the former governor's campaign, promised the ad would be in such heavy rotation that it should be hard for voters to miss.

The ad features an image of President Bill Clinton signing bipartisan welfare overhaul legislation in 1996 and video of people working. A narrator says:

"In 1996, President Clinton and a bipartisan Congress helped end welfare as we know it by requiring work for welfare. But on July 12, President Obama quietly announced a plan to gut welfare reform by dropping work requirements. Under Obama's plan, you wouldn't have to work and wouldn't have to train for a job. They would just send you your welfare check. And welfare-to-work goes back to being just plain old welfare. Mitt Romney will restore the work requirement because it works."

The ad seems meant partly to drive home the message for voters that Obama is no Clinton — in anticipation of the higher profile the former president will assume in Obama's re-election campaign in coming weeks. Clinton will be a headliner at the Democratic National Convention in Charlotte, N.C., for instance.

But it also raised welfare as an issue in a way reminiscent of how Reagan used it in 1980. Then, Reagan famously used the image of a welfare queen driving a Cadillac as a metaphor for how liberals and big government had run amok, throwing the money of hardworking Americans at lazy welfare recipients.

Texas Solicitor General Ted Cruz, the Tea Party-backed candidate, just won the Republican nomination for the U.S. Senate from the Lone Star State. On the Romney campaign conference call, he echoed some of the criticisms of welfare from the days before the 1996 overhaul:

"It hurts the recipients of welfare. The most compelling reason behind the bipartisan welfare reform that we saw is that helping those receiving government assistance to get jobs, stand on their own feet, fundamentally transforms their lives. We're not doing anybody a favor by giving them welfare in perpetuity and making them dependent on government."

The "welfare in perpetuity" line was a particular throwback to the days before the overhaul, since a key part of the law signed by Clinton placed time limits on how long such benefits could be received.

One of several responses Obama's campaign issued throughout the day came from spokeswoman Lis Smith:

"Mitt Romney continues to make statements that he knows are both untrue and hypocritical. The Obama administration, working with the Republican governors of states like Nevada and Utah, is giving states additional flexibility only if they move more people from welfare to work — not fewer. But as governor, Mitt Romney petitioned the federal government for waivers that would have let people stay on welfare for an indefinite period, ending welfare reform as we know it, and even created a program that handed out free cars to welfare recipients. These false and extremely hypocritical attacks demonstrate how Mitt Romney lacks the core strength and principles the nation needs in a President."

Republican governors in Nevada and Utah requested that the Obama administration offer greater flexibility. But Obama's and Romney's campaigns disagree on whether the governors were actually seeking flexibility on the work requirement.

The Obama campaign also directed reporters' attention to a BuzzFeed item by Andrew Kaczynski, who found circa-1997 comments from two Illinois Republicans praising Obama, then a state senator, for working across partly lines to help fashion welfare-to-work legislation in the Land of Lincoln.

Meanwhile, the new Romney attack is clearly meant to tap into public resentment regarding welfare recipients getting something for nothing. A recent Rasmussen Reports survey found that 83 percent of respondents supported the notion that adults able to work who are receiving welfare be required to get a job.

-- Updated below @ 5:45 pm ET --

In a conference call to further respond to the Romney campaign's charges, the Obama campaign had John Podesta, Clinton's White House chief of staff, join Obama deputy campaign manager Stephanie Cutter and James Kvaal, the campaign's policy director.

Podesta called the Romney ad "completely false", and he and Cutter explained that to obtain a waiver, a state would within a year need to increase by 20 percent their placements of recipients into work.

They stressed that the request Romney and other Republican governors signed in 2005 called for a much more expansive waiver than anything the Obama administration would allow, including lifting the federal law's time limits on how long welfare recipients could receive benefits.

When asked by a reporter to respond to Romney positioning himself as a truer defender of Clinton's legacy than Obama, Podesta responded:

"I'm always happy when people embrace the new Democratic policies of President Clinton. I just wish they'd tell the truth when they do so."

The Obama campaign also pushed hard to get across the idea that as governor Romney was more liberal when it came to welfare initiatives than his current position would suggest.

Kvall said:

"As governor of Massachusetts, Mitt Romney created a program that gave free cars to the states welfare recipients, that paid for the costs of their insurance, taxes, titles, registration, repairs, even their Triple A membership. And for people who transitioned to work lost their jobs and went back on welfare, they were allowed to keep their free car."

I've asked a Romney spokeswoman for a response to the Obama campaign's comments and will post it when I get it.

(Updated below at 5:55 PM ET)

Amanda Henneberg, a Romney spokeswoman, provided the following response to the Obama campaign's comments:

"Governor Romney has always been a strong believer in the principle that welfare recipients must work. As governor, he vigorously supported policies to strengthen work requirements and to facilitate the process of getting people off welfare and into a job. He believes that one of the key accomplishments of bipartisan welfare reform legislation was to reinforce the dignity that comes with work. The facts are clear – with the stroke of a pen, President Obama gutted the work requirement in welfare reform and, along with it, decades of progress on this critical issue."Copyright 2016 NPR. To see more, visit http://www.npr.org/.