Full of Secrets
Dan Emmett, a former Secret Service agent in the Presidential Protection Division who protected George H.W. Bush, Bill Clinton, and George W. Bush, has an illuminating essay published in the Wall Street Journal, which details the excitements and frustrations that come with protecting the president:
In terms of the actual physical experience, imagine something like this: Forgo sleep for 24 hours, skip lunch and dinner, stand outside of a house in the rain at 3 a.m. for several hours, take a cab to the airport and finally board a plane to a large city for a four-hour flight. Repeat this regimen for several days in a row. To make the simulation complete, you also need to fail to attend a child's birthday or graduation and miss the holidays or your wedding anniversary. [...]
Secret Service agents have an odd position in the White House. Agents are so physically close to the president that they hear and see almost everything the president sees and hears. Yet, unlike the presidential staff, agents stand silently and seldom offer input into situations other than those that are security-related. If asked by POTUS about a situation, especially political, the agent should be brief and friendly yet noncommittal. In most cases, any conversation between POTUS and agent should be over within seconds after its beginning. [Wall Street Journal]
For the full essay, which includes fascinating details about the challenges of protecting presidents who go jogging, head over to the Wall Street Journal.