Agents from the Presidential Protection Unit guard the innermost layer of security, ensuring the safety of the White House boss.

According to Mr. Jeffrey Robinson, co-author of the book `Standing Next to History: An Agent’s Life Inside the Secret Service` about the lives of secret service agents protecting the US president, agents and White House staff.

They have to deal with a lot of work, such as ensuring the airspace at the airport is always clear when the presidential plane lands, requesting the establishment of an escort vehicle team, determining the location of hospitals, and monitoring the situation.

Oregon Live quoted Mr. Ronald Kessler, author of many books about the US secret service, the Central Intelligence Agency (CIA), and the Federal Bureau of Investigation (FBI), saying that the presidential protection force still has to coordinate.

Service dogs are also an indispensable part of the US presidential protection team.

They also had to remove all vehicles parked on the streets surrounding the president’s residence to ensure that no one could place a car bomb near the president’s hotel, Mr. Robinson said.

An equally important task of secret service agents is to ensure that the president is always near field hospitals, a maximum of 10 minutes by car.

According to Robinson, Air Force One carrying the president will be accompanied by at least six other aircraft.

`Thousands of people are deployed every time the president moves,` Mr. Robinson said.

In addition, to keep the president as safe as possible, the routes his motorcade passes through will also be banned.

When the president arrives at the hotel, Secret Service agents may not let him in through the main entrance.

Secret Service agents must also check the identities and background records of all hotel employees where the president is staying, Kessler added.

Secret Service agents will check the entire presidential room before he enters.

Robinson revealed that secret service agents will build a three-layer security perimeter around the president.

When the US president travels, he often brings his own food, Robinson said.

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