PHILADELPHIA – Cases of union embezzlement, violence and intimidation certainly aren’t isolated to our nation’s public schools. Unions in many industries throughout our nation and the world readily employ thuggery to get their way.

A hotbed for union beat downs apparently is Philadelphia.

National Review reported that between 1974 and 2009, 143 incidents of union violence were reported by local media outlets, the National Right to Work Committee found.

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“It’s a grim roster that includes an unsuccessful murder attempt; a janitor losing an eye during a protest; the firebombing of company property; countless tires slashed; and business owners being threatened with a gun and with knives,” National Review’s story said.

The NRTWC estimated that for every union violence story reported by the media, 10 go unreported. That equates to 45 incidents per year – just in the city of so-called brotherly love.

Will that stat be taught during California’ Labor History Month?

National Review’s Jillian Kay Melchior told this story of an unidentified engineer at a construction site:

The engineer’s wife caught his brutal beating on camera.

Just seconds before, the couple had arrived at the open-shop construction site in downtown Philadelphia, walking past the cluster of union protesters who had congregated outside the fence.

As the engineer tried to enter the site through a tiny gap between a chain-link fence and a stone wall, the protesters rushed him, pressing the fence against his body and pinning him. The engineer shouted out, then howled, clutching the fence with both hands. His cries grew hysterical as he thrashed, first trying to escape, and then simply trying to shield himself. When the aggressors finally relented, he crumpled to the ground and passed out.

“It was terrifying,” the engineer tells me, asking to remain unnamed for fear of union retaliation. “I was concerned that if they pushed a little harder, my head would be crushed. Even after I was on the ground the Civil Affairs cop came up. Who knows what they would have done if he hadn’t been there?”

The engineer’s assault was caught on tape. But despite being charged with simple assault, reckless endangerment of another person, and conspiracy simple assault, two union members, Ryan P. Stewart and Philip J. Garraty, each got off with a $200.50 fine and 18 hours of community service.

This type of thing is not uncommon in the world of organized labor. If public schools are going to teach the history of the labor movement, as they’re doing this month in California, the ugly aspects should not be ignored.

Unless, of course, California’s union teachers want to give their students a falsely positive impression of unions. You don’t suppose they would do that, do you?

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To read more installments of “The Other Labor History: What Kids Won’t Learn,” click here.