When is a graduation speech a campaign speech?

When a politician turns it into one.

And while Vice President Joe Biden presumably won't directly solicit 2016 S.C. Democratic presidential primary votes in his 2014 commencement address for the University of South Carolina's business, public health, mass communications, nursing and pharmacy schools on May 9, he has already commenced his unofficial campaign for a promotion to the Oval Office.

Biden also long ago earned his reputation for repeatedly saying strange things that other politicians wouldn't say.

For instance: The then-sixth-term senator from Delaware visited Charleston 7½ years ago to lay groundwork for a 2008 White House bid. As a "Fox News Sunday" guest from here on Aug. 27, 2006, Biden offered a bizarre 19th century perspective on why he was confident about 21st century Southern support.

Host Chris Wallace: "As we've mentioned, you're in South Carolina right now, on the campaign trial. Thirty seconds or less, what kind of a chance would a Northeastern liberal like Joe Biden stand in the South if you were running in Democratic primaries against Southerners like Mark Warner and John Edwards?"

Biden: "Better than anybody else. You don't know my state. My state was a slave state. My state is a border state. My state has the eighth-largest black population in the country. My state is anything from a Northeast liberal state."

Yet Biden dropped out of the 2008 presidential race before he could test his "slave state" solidarity theory. And he's unlikely to play that "slave state" card again during next month's graduation speech at Colonial Life Arena in Columbia - or any other time.

Then again, few folks expected Biden to say that Mitt Romney, if elected president, was "going to let the big banks once again write their own rules, unchain Wall Street. He is going to put y'all back in chains."

But that's just what Biden told a largely black audience at a campaign rally in Danville, Va., on Aug. 14, 2012.

Space limitations preclude listing more examples from the vast volumes of Biden's verbal wonders of blunder.

Still, our vice president gave a dandy pep talk at Tuesday's anniversary memorial service for the victims of last year's Boston Marathon bombing.

And he's not the only politician who will pontificate at graduations next month. Among the other candidates spouting platitudes to the too-many scholars battling for too-few job opportunities: Sen. Tim Scott at the College of Charleston's May 10 commencement.

Biden's also not the only politician who has had some explaining to do about what he has said.

For example, Wisconsin Congressman Paul Ryan, who as Romney's running mate wanted to replace Biden, was accused of being racially insensitive for saying on a radio show last month:

"We have got this tailspin of culture in our inner cities, in particular, of men not working and just generations of men not even thinking about working or learning the value and the culture of work."

However, it evidently was OK for President Barack Obama to say basically the same thing in these words seven weeks ago:

"Fewer young black and Latino men participate in the labor force compared to young white men. And all of this translates into higher unemployment rates and poverty rates as adults."

Clearly, despite well-intentioned Americans' familiar appeals for candor in discussions of race, a double standard persists on who can say what about it.

And sadly, that's a predictable hangover in a country where many folks descend from slave owners and many others from slaves - and where Jim Crow remained a cruel Southern reality as recently as my boyhood.

For more insight on our nation's enduring racial divide, see columns on Page A11 by the Rev. Joseph A. Darby and Kathleen Parker.

Now for more insight on Biden's "slave state" reference:

In 1861, Delaware and three other states (Maryland, Kentucky and Missouri) where slavery was still legal stayed in the Union rather than joining the 11 slave states that seceded - starting with South Carolina in late 1860.

Back to the much more recent past for this graduation- test question:

What commencement speaker told the College of Charleston's Class of 2013 last May that "integrity, sacrifice and service" are "the ultimate path to a successful life"?

Answer: Glenn McConnell, whose successful bid to become the president of his alma mater (College of Charleston, Class of 1969) has sparked an ongoing uproar.

But whatever else you think of McConnell, know this:

That South Carolinian is not on record anywhere for ever having bragged about being from a "slave state."

Frank Wooten is assistant editor of The Post and Courier. His email is wooten@postandcourier.com.