By Andrea Burzynski

NEW YORK (Reuters) - International best-selling novelist Lionel Shriver's latest book is released on Thursday, but it isn't exactly new. She wrote it over 10 years ago.

"The New Republic" follows Shriver's best-selling works like "The Post-Birthday World" as well as "We Need to Talk About Kevin," the 2011 movie starring Tilda Swinton for which she was nominated for a best actress Golden Globe.

"The New Republic" tells the story of a corporate lawyer-turned-freelance journalist Edgar Kellogg who takes an assignment reporting about a fictional terrorist group on a Portuguese peninsula after the celebrated reporter before him mysteriously disappears.

As Edgar tries to prove his journalism chops and unravel the mystery surrounding his predecessor's demise, he also struggles to fill the social void left by the charismatic man who came before him and come to terms with his own shortcomings.

When she first wrote "The New Republic," Shriver, 54, said her then-modest sales record and what she perceived as America's disinterest in terrorism, in general, before the September 11 attacks made it impossible to find a publisher. Of course, much has changed since then - except for the book itself.

Shriver, who has shown a knack for anticipating hot topics like school shootings, maternal ambivalence and the complexities of healthcare in the U.S., said her original manuscript remains largely intact.

"If you're trying too hard to be super contemporary, you get overtaken by events," she told Reuters. "The world moves on."

Shiver said she waited until after the tenth anniversary of the September 11 attacks to release the novel because she feared that her light approach might be seen as being in poor taste.

It's a heavy subject, but it's intentionally addressed with a light touch. And I think that makes it more effective," she said. "I also think that humor is a much more nefarious weapon against terrorists at this point than just more denunciation. The one thing a terrorist can't stand is to be laughed at."

HUMOROUS APPROACH

Throughout her career, Shriver has made a habit of injecting drollery into serious topics such as school massacres, healthcare and marital troubles. She believes that a dose of humor, which she calls "the ultimate survival mechanism," makes heavy subjects more bearable both in life and in print.

"I find in general when I'm writing a book I try to keep myself amused in the process, and I hope I keep the reader amused," she said.

Though "The New Republic" often takes a satirical approach to politics, media, and the public's reaction to violent incidents, Shriver also has serious thoughts on the way governments handle terrorism.

"I think it's a terrible mistake to center foreign policy on terrorism," she said. "What's wrong with these people is not their politics and their points of view, it's that they blow people up."

Despite the drive to find meaning in random violent acts, Shriver believes the political and personal soul-searching that often follow such acts gives hardline militants more attention and power than they deserve.

"The trouble is that we take these things and we always want to draw lessons," she said. "There's a way in which we have to say 'that's bad,' and then move on."

(Reporting by Andrea Burzynski; Editing By Christine Kearney and Bob Tourtellotte)