And economists say drugs are part of the problem - but only a small part. They point to some simple and uncomfortable math: There are three unemployed workers actively seeking work for every available job in America, and Pennsylvania is slow to generate jobs.
"Our condition is a substantial and historic excess labor supply," said economist Paul Harrington, director of the Center for Labor Markets and Policy at Drexel University. "Other problems, like drugs, are small potatoes."
Besides, drug-testing experts say, fewer workers are testing positive for drugs on the job than in the past, and fewer in Pennsylvania than in the country as a whole.
The flap began during a monthly "Ask the Governor" program, recorded Monday by the website PAMatters.com. Corbett made his remark in connection with a discussion about jobs and the Marcellus Shale industry.
"It was a statement taken out of context for political benefit," said Christine Cronkright, a Corbett spokeswoman. She added that when Corbett referred to people failing drug tests, he was saying it was a concern "more in manufacturing than anywhere else."
During the program, as Cronkright noted, Corbett also addressed larger issues of the economy, saying "we need to get people ... trained for the jobs of the 21st century" and praising community colleges for moving in that direction.
But the comment that sparked some people's ire was, "There are many employers that say . . . we are looking for people, but we can't find anybody that, that has passed a drug test, a lot of them, and that's a concern for me, because we're having a serious problem with that."
Those words "implied if you're out of work, there's something wrong with you," said Cheryl Spaulding, president of Joseph's People, which supports unemployed people, many of them over 40 and with advanced degrees, in job searches.
Dentral Smith, 45, an unemployed social worker in West Philadelphia, said Corbett's remark betrayed "his ignorance of his constituents."
And John Dodds, director of the Philadelphia Unemployment Project, said Corbett was guilty of the "worst kind of stereotyping, covering up his own mistakes with the economy by saying the victims of the economy are the cause."
The bashing of the governor didn't sit well with Gene Barr, president of the Pennsylvania Chamber of Business and Industry. "We frequently hear from our member companies that is absolutely a problem for them," he said.
David Taylor, executive director of the Pennsylvania Manufacturers' Association, labeled Corbett "100 percent correct," saying drug-test failure "is a recurring theme in workforce preparedness."
Dawn Fuchs, chief executive of Weavertown Environmental Group, which hauls water and wastewater for Marcellus gas drillers, said jobs are going begging as employers try to find qualified applicants. Many job-seekers don't even apply for work after being told a company tests for drugs, she said.
Failed drug tests are "one of the top ... reasons for individuals' not completing applications or entering" the ShaleNET program at Westmoreland County Community College, said Byron Kohut, director of the program, used for recruitment and training in the natural-gas industry.
Employers struggle daily with the drug problem, said Scott Wagner, a York waste-company executive and a conservative activist. "I would go on to say that 25 percent of the unemployed in this country are unemployable," he said in a statement. "Many cannot pass drug tests, lack the drive and work ethic to get out of bed in the morning, or no longer have the self-confidence needed to get a job after being unemployed for so long."
The complaint about failed drug tests is often repeated among employers in the "echo chamber" of the manufacturing sector, said Mark Zandi, chief economist with Moody's Analytics. But "there isn't good data" to support the claim, he said.
What's true nowadays is that employers are "more picky," Zandi said, unwilling to hire and train those who don't "fit exactly what they're looking for."
He said one theory is that employers who laid off human-resources executives no longer have a strong structure for recruiting workers.
Georgetown University economist Harry Holzer pointed out that the nation faces a near-8-percent unemployment rate with a 2.8 percent job-vacancy rate - an extraordinarily high level.
Most vacancies can't be explained by drug tests, Holzer said. "A lot of companies are posting job vacancies but not working hard to fill them, being very choosy about employees," he said.
Compounding problems are skills gaps - workers not trained well enough to do increasingly more sophisticated manufacturing jobs, Holzer said.
Corbett made the same point in the interview.
Overall, Drexel's Harrington said he has found in his research, 75 percent of unemployment in Pennsylvania is linked to the "job deficit": There aren't enough openings. He estimated that 25 percent is due to factors such as employees lacking requisite skills, proving undependable - or having drug and alcohol problems.
The nationwide rate of workers testing positive for drugs declined between 1988 and mid-2012 from nearly 14 percent to about 4, according to Quest Diagnostics, a leading provider of drug and medical tests.
The reason: fear of drug testing, Quest officials said.
In Pennsylvania, the rate for workers testing positive for drugs is 3.8 percent, compared with the overall U.S. workforce figure of 4.1 percent, they said.
As for the debate over Corbett's remark, Zandi said governors need to take care not to simplify issues from the "bully pulpit." Still, the economist said, "my guess is he knows it's a much more complicated issue."
Contact Alfred Lubrano at 215-854-4969 or firstname.lastname@example.org.
Contributing to this article were staff writers Bob Fernandez, Andrew Maykuth, Kristen A. Graham, Susan Snyder, Linda Loyd, Mike Armstrong, Joseph M. DiStefano, and Amy Worden.