It’s disconcerting for a publisher to discover that a horrific tragedy has made one of its current titles more relevant. But that’s what happened to the Cato Institute when 11 journalists at Charlie Hebdo and a police officer were murdered by Islamist extremists.

In November, we published The Tyranny of Silence, by Flemming Rose, the editor at the Danish newspaper Jyllands-Posten. Rose stirred up controversy in 2005 by publishing cartoons of Muhammad that led to protests, petitions, and an investigation by Danish prosecutors. More tragically, there were death threats to Rose and the cartoonists, an armed intruder in cartoonist Kurt Westergaard’s house, and more than 200 deaths in riots and violence in the Middle East and Africa.

Rose published the Danish edition of Tyranny of Silence, a book about the controversy and the future of free speech, in 2010. I was surprised to discover in 2013 that the manuscript had been translated into English but had not found a publisher. I brought it to the attention of John Samples, the editor-publisher of Cato Institute Press, who began to explore publication.

We had three questions in mind: safety, of course; the quality of the manuscript; and whether Rose was anti-Muslim or genuinely an advocate of free speech and provocative journalism.

We determined that the publication of the book had not generated any violence in Denmark, and that the controversy over the cartoons had generally subsided in the nine or so years since they had been published. The manuscript was compelling, well written, and well translated. And my contacts in Denmark and Europe assured me that Rose was a genuine liberal with a strong anti-authoritarian bent, sharpened during his years as a reporter in the Soviet Union.

Given all that, the book was a natural fit for the Cato Institute. Since our founding in 1977, we’ve been committed to the libertarian values of individual liberty, limited government, free markets, and peace. We take our name from Cato’s Letters, a series of 18th-century newspaper essays by John Trenchard and Thomas Gordon that were enormously influential in shaping the ideas of the American Revolution. In essay #15, they set out one of their basic principles: “Without freedom of thought, there can be no such thing as wisdom; and no such thing as publick liberty.... In those wretched countries where a man can not call his tongue his own, he can scarce call any thing else his own.”

So we published the book, with a foreword by Nat Hentoff, perhaps the greatest First Amendment defender of the past generation and now a senior fellow at Cato. When The Tyranny of Silence appeared in November 2014, the response was good. On a brief visit to the United States, Rose spoke at Cato, the Newseum, and Philadelphia’s Pen and Pencil Club; he was interviewed by the Washington Post and did a Reddit AMA (Ask Me Anything) that garnered more than 200,000 page views.

Then came the horrors of January 7 in Paris. Suddenly the book was directly relevant to the crisis dominating world headlines: offensive cartoons, murdered journalists, the reaction of the West, the nature of liberal society. Suddenly everybody was calling: Time, the New York Times, CBS This Morning, ABC’s This Week, CNN, BBC, the Daily Mail, El Pais, the New Republic, the Financial Times. The Tyranny of Silence’s Kindle edition shot to #1 on Amazon’s Civil Rights and Liberties list and also reached single digits on its Censorship, Political Freedom list, as well as similar lists in France, Germany, and Australia. We ordered a second printing.

Throughout these past few busy days, though, we’ve been deeply saddened by the events that brought such attention to our book.

Writing at Time.com, Cato senior fellow Walter Olson declared, “If you defend freedom of speech today, realize that ‘blasphemy’ is its front line, in Paris and the world.

"For years, blasphemy laws were assumed to be a relic of the past, but laws accomplishing much of the same effect are once again on the march in Europe, banning 'defamation of religion,' insults to religious beliefs, or overly vigorous criticism of other people’s religions when defined as 'hate speech.' This must go no further. One way we can honor Charb, Cabu, Wolinski, Tignous, and the others who were killed January 7 is by lifting legal constraints on what their successors tomorrow can draw and write."

And as Olson suggests, the Cato Institute will continue to stand for untrammeled freedom of speech as a foundational element of a free society.

David Boaz is executive v-p of the Cato Institute and author of The Libertarian Mind, to be published by Simon & Schuster on February 10.