Steve Sack, the Star Tribune's Pulitzer Prize-winning editorial cartoonist, was recently joined by three fellow cartoonists on a keynote panel at the College Media Association convention in New York. Among the 600 students and faculty advisers in attendance were an unknown number of undercover NYPD officers. More conspicuous were the metal detectors and the eight security guards who were required to be hired at a cost of $4,000.

Whether this is the new normal after the attacks on the satirical newspaper Charlie Hebdo in Paris and a free-speech event in Copenhagen (a kosher market in Paris and a synagogue in Copenhagen were also targeted) remains to be seen. But it's clear that the attacks are having an impact on journalism, art and the profession of cartooning.

Similar events are being canceled or curtailed worldwide, said Daryl Cagle, a fellow panelist who runs a cartoon syndicate. "There is renewed interest and concern about this constraint on our freedom of the press in light of the attacks. It's grim, because the terrorists win. And they make dealing with cartoonists expensive, a hassle and a concern, and it's had a real impact on our business."

And it's not just terrorists who are winning. Worldwide, repressive regimes have targeted cartoonists, according to a recent Reporters Without Borders report, "The ever more dangerous profession of cartoonist."

Eight cartoonists from four continents who were among many persecuted for their work were highlighted. Among them was Ali Ferzat, who drew critical cartoons of Syrian President Bashar Assad. As Syria's Arab Spring bloomed in 2011, Ferzat was kidnapped. His abductors gave him to pro-Assad militia members, who burned his body with cigarettes before crushing his drawing hand and leaving him hooded and helpless on a Syrian road. Ferzat, who now lives — and works — in exile in Kuwait, was awarded the European Parliament's Sakharov Prize for Freedom of Expression.

"Despots don't have a sense of humor," Cagle said, adding that in authoritarian societies, cartoonists can be "like the canary in the coal mine."

Yet despite the risks, despots continue to be depicted in cartoons that pack a punch (and a punchline). The impact of cartoonists' work varies from country to country. In many nations, Cagle said, cartoonists are the most important voices in the public debate, so "it's no surprise that cartoons would be the flash point of a clash of civilizations."

This proverbial clash became a literal one in Paris. Sack, who had previously met two of the Charlie Hebdo cartoonists at a convention in France, said the Charlie Hebdo cartooning style was "almost a dare. Is that reckless? Maybe. Or is it making a valiant stand on something that is important? And free speech is important. If our society can be limited by the views of another society, or religion, that takes away an important element of our freedom."

Indeed, there was a "worldwide deterioration in media freedom in 2014," according to another analysis by Reporters Without Borders. That includes cartoons. A few offend because they depict the prophet Mohammed. But more are about (and get under the thin skins of) political leaders.

"Cartoons are different from an opinion column or an editorial because it doesn't acknowledge the arguments of the other side — it just presents one point of view," Sack said. "It's not a debate, it's a statement. On top of that, it is visual and very potent. And it can also include elements of humor and mockery, which can be perceived as personal."

They're potent in America, too. But they're expected and mostly accepted. "My entire life I expected I could express myself with my art as I please," Sack said, reflecting on his 38 years of cartooning. He added: "Cartoonists in America have had it pretty good, although they do get hate mail, with some of it pretty vile, but that comes with the territory."

Cagle has also endured website attacks, which hackers began a few weeks before the Charlie Hebdo attacks. His site is already banned in Iran and other countries. The attacks have increased his website costs by about $85,000, and Cagle said has started a crowdfunding campaign to defray expenses. Some European sites, he said, have been similarly singled out.

Sack, who in the last two years has spoken at cartoon events in mainland China, Hong Kong and France (where the American delegation was presented with the convention's traditional award — a live cow), said that cartoonists have a kinship that transcends language, location and ideology.

"All cartoonists are compatriots," Sack said. "It's very subjective. It's an art, a very individual thing, so naturally we feel a kinship toward any other cartoonist because they're facing the same problems and challenges — it doesn't matter what ideology."

This kinship will be needed, since it's highly unlikely that cartoonists will back off, despite the rising pressure. "The 'freedom barometer' is whether a cartoonist can draw the president of his country," Cagle said. "Cartoonists are a window on the world of freedom of press all over the world."

Like all other free expression, it's a window that must not be allowed to be closed.

John Rash is a Star Tribune editorial writer and columnist. The Rash Report can be heard at 8:20 a.m. Fridays on WCCO Radio, 830-AM. On Twitter: @rashreport.