• Publisher of Harper's Magazine and Board Chairman of the tax-exempt foundation that owns it
• Grandson of the late billionaire John D. MacArthur, whose family foundation rescued Harper's Magazine from extinction and made him its publisher
• Objected to claims that Soviet dictator Joseph Stalin was as evil as Adolph Hitler

John R. "Rick" MacArthur is the Publisher of Harper's Magazine and the Board Chairman of the Harper's Magazine Foundation, which owns the periodical as well as the Harpers.org website and the closely-linked book publisher Franklin Square Press.

Born in June 1956, Rick MacArthur grew up in the wealthy Chicago suburb of Winnetka, Illinois. His great-uncle Charles MacArthur co-wrote with Ben Hecht the famous newspaper comedy The Front Page. Rick's grandfather was the billionaire real-estate and insurance tycoon John D. MacArthur. At age 12, Rick MacArthur worked zealously for the 1968 presidential campaign of Democrat Eugene McCarthy. In his teens he worked for the campaigns of presidential hopeful George McGovern and congressman Abner Mikva.

"We were a liberal, pro-civil rights, anti-Vietnam War family," MacArthur told one interviewer. "My mother's foreign, my father's left-wing. We didn't involve ourselves in the same activities as the WASP Republicans."

Rick MacArthur's father, Roderick, was far to the left of his own father, John, and was disinherited. Rick MacArthur says he "knew from the age of 8 or 9" that his branch of the family had been written out of his grandfather's will. Roderick would become a millionaire through ownership of the Bradford Exchange, which sells collector plates, and Hammacher Schlemmer stores. (His children, including Rick, inherited these businesses after Roderick's death in 1984.)  Roderick also had a seat on the Board of the John D. and Catherine T. MacArthur Foundation; threatening to generate negative publicity by suing other Board members, he was able to pressure them into adding left-leaning Board members and funding projects he favored.

Rick MacArthur worked as a reporter for The Wall Street Journal (1977), the Washington Star (1978), The Bergen Record (1978–1979), and the Chicago Sun-Times (1979–1982). He was also an assistant foreign editor at United Press International in 1982.

In 1980, 23-year-old son Rick MacArthur and his father persuaded the Boards of the MacArthur Foundation and the Atlantic Richfield Company to create and fund a Harper's Magazine Foundation, which for $250,000 purchased the magazine.

With his father's help, Rick MacArthur maneuvered to take control of this new foundation, which he now heads. As Harper's publisher he reinstalled previously-fired editor Lewis H. Lapham. Together they reshaped the magazine in 1985 into what some have called a "Reader's Digest for intellectuals," with shorter articles and quotable features such as the Harper's Index of odd factoids. As of 2004, Harper's claimed a combined circulation of 210,000 and in most years continued to lose money.

Under Rick MacArthur's control, Harper's remains a media outlet for the work of leftwing writers like Nicholas Von Hoffman, Barbara Ehrenreich, Jonathan Schell, Earl Shorris, and longtime book reviewer for The Nation, John Leonard.

MacArthur has made no secret of what he describes as his "naïve liberal" views. An ardent foe of the death penalty and a booster of leftist causes, he is the author of two books, both published by the University of California Press: The Selling of "Free Trade": NAFTA, Washington and the Subversion of American Democracy (2001), and Second Front: Censorship and Propaganda in the Gulf War (1993, with an updated edition published in 2004).

As a reporter, MacArthur broke the story that during the Gulf War, the young woman who accused Saddam Hussein's troops of stealing Kuwaiti hospital incubators (and discarding the babies kept alive in them) was the daughter of a Kuwaiti diplomat making anti-Iraq propaganda.

The December 13, 1998 edition of Harper’s featured an article by MacArthur titled "Neo-McCarthyism and the New Cold War Hangover." This polemic was against the "emboldened reactionaries" who had declared that the Soviet Marxist dictator Joseph Stalin was just as evil as the German Nazi dictator Adolf Hitler. "It is false," argued MacArthur, "to make Stalin's indirect killings born of political ideology equal to Hitler's direct murder born of hatred for an entire race."  "If [Communist] Stalin was as bad as Hitler," wrote MacArthur, "then [anti-Communist Senator Joseph] McCarthy's depredations against civil liberties and common decency become more palatable."

"I suspect," added MacArthur, "[that] today's neo-anti-communist movement is in part fueled by a profound desire to wipe out the tattered remnants of both the old and the new left. Not satisfied with Ronald's Reagan's reversal of Franklin Roosevelt's New Deal legacy (or Mikhail Gorbachev's reversal of Lenin's), the emboldened reactionaries in U.S. politics, media and academia are out to settle scores with their counterparts who opposed the madness of the Vietnam War, the crime syndicate run by Richard Nixon and the racist laws of the former slave-holding states."