The secret mercenary of the CIA Mitch Rapp is crushed by the bride's loss as a result of the terrorist attack. The deputy director of the CIA appoints Stan Hurley to train a grief-stricken but seriously-minded Mitch to prevent terrorist operations and hunt criminals. Together they explore a wave, at first glance, of random attacks on military and civilian objects. But later the partners will have to unite with the Turkish agent in order to prevent the beginning of the Third World War in the Middle East.
There's plenty of talk about American Sins in American Assassin, but none of it changes the fact that the bad guys want to do bad things and must be stopped, so there really isn't much point to all that chatter.