Tom Clancy's Chain of Command

President Jack Ryan always feared the greatest threat would be to the nation - from Russia, China or an act of international terrorism. Never in his wildest dreams could he imagine it could be so ...

President Jack Ryan always feared the greatest threat would be to the nation - from Russia, China or an act of international terrorism. Never in his wildest dreams could he imagine it could be so personal - so directed at him.
As the President scrambles to fight back, regain control and save those he loves, the men and women protecting him must work fast to solve three mysteries:
Who has the power to do this?
Why attack the President of the US?
And how can they be found and stopped?