These people really start to come in during book 2, which takes place at the White House. After that, the president and his family, along with some secret service agents begin to play a larger part in the story.
The presidents and his people are a great help, espicially since the president used to be the director of the CIA. So now SOS has some presidential help in the form of both men and materials. These people are a help and so interesting as well. The author most definitly did a good job creating his presidential family.