The answer is, naturally, life. Imagination plays a role, to be sure, but life provides the necessary inspiration to fill the pages with intrigue, conspiracy, corruption, backroom-dealing, and all that, which delivers the necessary thrills to keep the book pages turning:
I think the American government has gone rogue and no longer follows the will of the people. There is no reliable independent oversight of the CIA or the National Security Agency. The telephone switching systems are run by Israeli companies with direct ties to Mossad, who intercepts calls and intelligence, and Congress does nothing.
Presidents use lies to initiate wars, and Congress does nothing.
The U.S. engages in a so-called war on drugs for 40 years, spending more than what was spent on World War II with the result being more drugs, more citizens in jail, the U.S. arming drug gangs, the U.S. being invaded by those gangs, and nothing done about it. Drug money is laundered by the biggest banks, funding clandestine programs, and used to buy off police, enforcement agents, and politicians. The real solution is decriminalization, regulation, tax, and treatment. If we did that, all drug violence and crime would end. Politicians, banks, intelligence agencies, and enforcement agencies don't want that because they are making too much money off the drug war and will fight tooth and nail to keep it going.
The so-called war on terror is an unending war on an abstract idea that is impossible to "win" as the number of things called "terror" increase at officials' whims. It is not a coordinated activity by a shadowy group, unless you are talking about the CIA, which created al Qaeda. The so-called "terror events" are staged by our intelligence services in coordination with the media to scare the public and ram through unconstitutional laws that take away our liberty.
All the airport "security measures" are theatre used to intimidate and scare the public, reducing us to submissive concentration camp slaves to have the most intimate parts of our persons and our loved ones radiated and groped. And the criminal congress-persons go along with it. Too much money is being made to end it, and it is one more step to control and a police state.
Our politicians are part of this cabal of control. We all need to wake up and take action before it gets any worse. Speak up. Push back. We still have freedoms, and we need to use them before this horrid police state goes any further."