When I read a promotion for “Purpose of Evasion,” the first in a new series of spy fiction from author J.A. Walsh , the description of a novel that revealed America’s vulnerability to the unlikely confluence of foreign-inspired domestic terrorism and homegrown discontent intrigued me. This was more or less the same world that my wife Kate and I had lived in during our time in the Middle East.

The first time I realized that I had developed a heightened awareness of personal security in public was a sunny day in 2004, when my wife and I emerged from the subway at Downtown Crossing to visit a friend who worked nearby. As we stood at the T entrance and looked around, we were terrified. There were crowds walking with backpacks, garbage cans set up to keep the area tidy, and not a single armed security guard or bomb-sniffing dog anywhere.

I lived with my family in Jerusalem from 2002 – 2007, during the height of what’s known now as the Second Palestinian Intifada. By the end of the summer 2004, when we were visiting with family and friends in Boston, we had experienced more than 80 bombings of buses, university cafeterias, shops and other locations somewhere in Israel or the West Bank. Just about every public space in Jerusalem, and throughout much of the country, was cordoned off. Police with machine guns stood guard while pedestrians and shoppers were asked to open their bags and empty their pockets so they could be “wanded” with a metal detector.

I don’t think about our experience from that time much anymore. We’ve been back in the U.S. since 2010. But it came flooding back to me when I read Walsh’s novel and saw America through the eyes of his protagonist, a Muslim-American intelligence officer who, when looking out at an idyllic scene on the California coast, sees all the ways our daily routines might be disrupted or destroyed by those who want to do us harm.

I asked Walsh and his companion on book tour, William Gavin, a former FBI Assistant Director, if this novel was intended to educate, save or scare American readers.

“It’s all of the above. It has to be to get the job done,” Gavin answered.

» See Walsh's talk at Wellesley Books, recorded by WGBH's Forum Network.