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In a rare public moment, Charles Koch, one of the most prominent Republican mega-donors and one-half of the Koch brothers duo, spoke out this morning - not against Democrats or liberals - but against "collectivists," saying they "promise heaven but deliver hell."

Koch penned the scathing opinion piece in the Wall Street Journal just a day after a major decision from the Supreme Court opened the door for wealthy Americans to spend more money on campaigns, drawing praise from the right and criticism from the left.

"Collectivists" isn't a word that's used often in a country usually divided by "conservatives" and "liberals," but Koch uses the word four times in his op-ed. He doesn't mention either political party by name in the piece.

He even gives us a definition: "Those who stand for government control of the means of production and how people live their lives."

One of those examples of "government control" that Koch points his finger at: Obamacare.

"The more government tries to control, the greater the disaster, as shown by the current health-care debacle," he wrote. "Our critics would have you believe we're 'un-American' and trying to 'rig the system.'"

Major political donors - like the Koch brothers, Sheldon Adelson or George Soros - spend most of their time trying to stay out of the public eye, making this op-ed an uncommon glimpse into the mind of one of the most influential people in campaign finance.

The op-ed piece grabbed the attention of senators on both sides of the aisle.

Sen. Jerry Moran, R-Kan., chair of the National Republican Senatorial Committee, read the article by the Kansas-based businessman verbatim from the Senate floor.

"Unfortunately, in the political discourse of our country, Koch Industries and its owners are often subject to attack," Moran said. "I commend that opinion piece and its thoughts to my colleagues in the Senate."

But Sen. Majority Leader Harry Reid, D-Nev., wasn't having it.

"The reason that I felt so good about [the op-ed piece]: I think I must be getting under their skin," said Reid, who has often publicly linking the Koch brothers to GOP legislative interests. "These two men are a pair of shadow billionaires, spending millions of dollars to right our political system, and who does it help? Them."