For anyone whose knowledge of history extends beyond the current season of "Keeping Up with the Kardashians" or the latest instant replay of an NFL game, the four days of meetings involving Iran's president Hassan Rouhani, European leaders and businesses should remind people we have seen this show before.

Rouhani's state visit, the first by an Iranian president in nearly 20 years, follows the lifting of economic sanctions against Iran, the world's leading supporter of terrorism. Corporate giants and politicians are salivating at the prospect of doing business with a regime led by a man who has referred to Israel as "an old wound" that "should be removed."

There is plenty of money to be made in deals with the devil, but at what cost? In the 1930s when European and American businesses traded with the Nazis, the rationale seemed to be, "If we don't sell to them, someone else will." That amoral view, no doubt, contributed to the slaughter of an estimated 11 million people. Six million of these were Jews.

Re-visiting this hall of shame ought to at least give corporate and political bodies pause, when dealing with a regime that seems perfectly willing to finish the job Hitler and his brownshirts started. Have they learned so little from history that they are willing to repeat it?

Writing on Investopedia.com, Greg McFarlane offers a caveat to some of the businesses that purposely, or unknowingly, supported the Nazis: "By virtue of Hitler taking complete control of the most powerful country on the European continent, practically every existing business entity in Germany meant supporting Hitler, so it's not fair to frame all these businesses as enthusiastic Nazi collaborators."

Perhaps not, but like the majority of the German people, it is safe to say that quite a number of corporations ignored what the Nazis were doing so long as they could continue to do business and make a profit.

One of those companies was Siemens, the largest engineering company in Europe. About Siemens McFarlane writes: "The company forced slaves to manufacture components for the rockets that ended up raining down on London and Antwerp, Belgium, in short order. In the early 21st century, Siemens began to pay reparations to the workers it had paid nary a pfennig to 55 years earlier."

Will companies signing up to do business with Iran be shamed and perhaps forced by law at a future date to pay reparations to the families of those killed by Islamic terrorists funded by the Iranian regime?

IG Farben was another company that dealt with Nazi Germany. The company licensed to various companies the pesticide Zyklon B, which was used to suffocate millions in the death camps. "In 1951," notes McFarlane, "when the victors partitioned Germany, the Western Allies restored IG Farben into its original components," which included BASF, maker of cassette tapes. "Today, BASF continues to trade as one of the featured securities on the Frankfurt Stock Exchange, with a market capitalization of $60 billion."

A line from "The Godfather" seems an appropriate analogy. Just before someone is assassinated he is told, "Nothing personal, it's strictly business."

In a twist on this theme, Deutsche Bank in 1998 accepted "moral responsibility" for its dealings with the Nazis. These dealings included knowingly buying gold taken from people murdered in the camps.

What would be the morally responsible approach to Iran? Because the regime is complicit in the use of Improvised Explosive Devices (IEDs), which have led to the deaths of American servicemen and women, the morally responsible thing to do is not to conduct business with Iran.

Given the depths to which human nature appears to have sunk, however, that is unlikely to happen. After all, it's strictly business, right?

Cal Thomas is America's most widely syndicated op-ed columnist. He joined Fox News Channel in 1997 as a political contributor. His latest book is "What Works: Common Sense Solutions for a Stronger America" is available in bookstores now. Readers may email Cal Thomas at tcaeditors@tribune.com.