One of the interesting things about first millennium Britain is the role of cleverness in maintaining the family line. The shrewd rulers had to be both cunning and powerful, in order to maintain the family position. The ruling clans were always fighting among themselves and plotting against the other families. Much like the Old West, getting killed by treachery was more common than getting killed in single combat.

That came to mind when reading this story about that odious toad, Al Sharpton.

A drug trafficker who worked for Al Sharpton’s nonprofit in the 1980s said that despite the preacher’s denials, he was eager to get a slice of the lucrative drug deal captured on FBI surveillance video.

“It was greed. He just wanted money,” Robert Curington, 72, told The Post during a two-day interview at his North Carolina home, detailing for the first time how Sharpton stepped into the FBI’s trap — and was then forced to become a federal informant.

Sharpton has said he showed interest in the drug deal only because he feared the undercover agent was armed. He also claimed that he snitched for the feds — as first reported by The Smoking Gun this week — because the mob was threatening him.

Curington called all of that a tall tale.

He instead provided a detailed account of how Sharpton wined and dined a man he thought was a South American drug lord — and said Sharpton met him not just once, but three times.

Sharpton’s saga began in the Manhattan offices of boisterous boxing big shot Don King in 1983, Curington said.

An unnamed felon trying to duck a 30-year prison sentence promised the feds he could help them nail King on coke-dealing charges.

An undercover FBI agent, using the name Victor Quintana, set up a meeting with King to discuss a boxing match in the Bahamas — but King had a bad feeling about the potential business partner and pawned him off on Sharpton.

Don King is an exceptionally clever and cunning person. In fact, he is in the top-1% category. You will meet few men as cunning and sly as King. It is how he avoided the clutches of the FBI for five decades, despite being a criminal. It is how he maneuvered the Mafia out of boxing and largely ran the sport for decades – without killing anyone or going to prison. That’s an amazing accomplishment. Few mobsters ever die of old age and outside of prison. King is in a very small club.

The multidimensional thinking at work here is impressive. If Quintana was legitimate, King would get his piece as Sharpton was his guy. If the guys was just a crook, then Sharpton would get fleeced, not King. If the guy was a cop, then King avoids the FBI trap and Sharpton is out of the way without King getting his hands dirty. Intuitively, King saw the probabilities and charted the course most likely to benefit him. Sharpton, a first rate grifter in his own right, was a piker compared to King.

Then we have this.. The casinos do more to guard against cheating than any organization on earth. They bring all the toys to the party. They use surveillance, facial recognition, statistics, behavior sciences, you name it. If it can be used to catch cheaters, they have it. Talk to anyone working at the higher levels of casino security and you are talking to someone operating at a level only found in the upper reaches of the NSA and MI6. They are that good.

Despite this, exceptionally clever men find a way to beat the house. The cheat has to be right once, while the house has to be right every time. A small mistake like a defect in the playing cards can cost the house millions. The scammers have a million tricks to get the edge on the legitimate operator. They are full-time scammers, dedicating their life to finding the open door to exploit. Their targets – and the scammers know this – are part-time defenders, therefore never as good as the scammers.

There’s a lesson there that undermines all of the “isms.” Whether it is socialism, Marxism or libertarianism, they depend on people voluntarily going along with the spirit of the program. It is why socialism and Marxism always end in a blood bath. The clever fraction can’t stop gaming the system, It is their nature. Once the socialists or Marxists get this, they start killing the uncooperative. If libertarians ever gained control of a country, I suspect it would end the same way.