Consent to Kill book by Vince Flynn

For years, Mitch Rapp's bold actions have saved the lives of countless Americans. He has killed with impunity, tortured to avert disaster, and shown he will do whatever it takes to prevent terrorists from fulfilling their bloody wishes. His battles for peace and freedom have made him a hero to many, and an enemy to countless more. In the tangled, duplicitous world of espionage, there are those, even among America's allies, who want to see Mitch Rapp eliminated. They have decided the time has come.Now, the powerful father of a dead terrorist demands vengeance in its simplest form -- an eye for an eye, and Rapp instantly becomes the target of an international conspiracy. This time, he must use all of his vigilance and determination to save himself before he can turn his fury on those who have dared to betray him.