Enemy of the State by Vince Flynn/Kyle Mills

CIA operative extraordinaire Mitch Rapp is called to the White House late at night. The president is furious at Saudi Arabia and its perceived support of ISIS and he wants Mitch to do something about it--but off the books with no CIA support and no rescue if things go wrong. Mitch agrees and gathers a ragtag band to help him but of course things go wrong and he finds himself up against the wily head of Saudi intelligence--who is in fact a secret ISIS supporter. He is actively trying to frame Mitch for a series of murders to protect his own secrets and soon Mitch is regarded as an enemy of the state with limited means of proving his innocence. It's a real nail-biter of a tale.

Kyle Mills has done a good job with this series since the death of creator Vince Flynn.