Nitro Express (the Ben Blackshaw Series)

Holed up in a frigid New York City basement lair, Ben Blackshaw gets a coded distress call from his former commanding officer. The new mission takes Blackshaw on an international manhunt for a mysterious sniper. To launch the mission, Blackshaw is secretly flown across the country in an unmanned drone. When the UAV's encrypted guidance system is hacked by a sleeper cell of terrorists, the plane crashes, delivering Blackshaw into the hands of gunmen intent on killing him. He barely survives this opening skirmish, only to come under fire on a Los Angeles rooftop from the rogue sniper. His former CO, and two innocent bystanders are cut down in the barrage of bullets. Racked with grief, driven by guilt, Blackshaw reconnects with his old friend, Knocker Ellis Hogan, and together they try to lead the murderer away from populated areas before making the kill. The chase leapfrogs from the high Chilean desert to the icy wastes of northern Canada. At every turn, the killer slips away from their traps like a ghost. Along the way, Blackshaw learns that the sniper's deadly work is directed from the highest offices of the United States Government, and is part of a larger conspiracy to ignite a genocidal war-for-profit in South America. After Ellis is gravely wounded, Blackshaw makes a final stand on a wrecked ship in the Chesapeake Bay, only to discover that the killer's identity could make completing the mission next to impossible