In that enterprise his partner was the erstwhile Senator and presidential candidate Gary Hart. The end product, a taut and plausible political thriller, was called the Double Man. The title sums up the man: William Cohen, literatus of Capitol Hill, student of Latin, Hebrew and Spanish and no mean dabbler in poetry. And William Cohen the defence and security policy expert, now to be President Bill Clinton's Secretary of Defense.
The job was unexpected. Just a couple of months ago, after he had announced he was leaving Congress out of disgust at its bickering and meanness, the 18-year Senator from Maine reeled off to an interviewer a list of alternative careers. Among them, more thrillers, a job with a law firm, or setting up his own intelligence and defence consulting business. But then the President called. Would he consider working in a genuinely bipartisan national security team for a second Clinton term?
"It's a job where you lose your personal life, your privacy, your family," says the outgoing Defense Secretary William Perry, the most travelled Pentagon chief in history, who in 1996 has logged more than 200,000 miles. To it, Mr Cohen brings the keenest of minds and a reputation of one of the leading lights on the Senate Armed Services and Intelligence Committees.
But a man who must now run a bureaucracy of 3 million people and an annual budget of over $250bn has never run a business or served in the military.
In the Senate his popularity is huge. Even among Republican conservatives, his vote as a freshman Representative in 1974 for articles of impeachment against Richard Nixon, and his fierce criticism of Ronald Reagan in the Iran-Contra affair 12 years later, are badges of honour.
Since then Mr Cohen has grown into an eminence grise of US defence thinking, opposing the extravagant B-2 stealth bomber while searching for a doctrine to guide US military involvements in the post-Cold War world. And though he has never been in uniform, lines from A Baker's Nickel, the volume of poetry he published in 1986, suggest he is fully aware of the consequences of a failure by humankind to keep the peace:
"So when the earth goes red with a thousand suns, you can fire your light into the breast of sky a thousand times, star-drilled into all the hydrogen- headed monsters that rise up from earth and sea contemplating great catastrophe."