When the president of the United States visits China this week - the primary global rival to American supremacy almost 7,000 miles away - it takes a beast.

That means flying a $1.5 million, 20,000-pound armored Cadillac loaded with eight-inch thick armor, tear gas cannons, night vision, a sealed oxygen supply, and Donald Trump's blood type on ice.

And that's just to transport him from the airport. 

Between White House aides, Cabinet members, Secret Service, State Department officials, military personnel and journalists, roughly 900 people from the US delegation will accompany the president on his trip, according to the US-China Business Council. Shepherding them all over will take countless flights. 

At least two US Air Force C-17 Globemasters have been spotted in Beijing this week - the same type of craft that's used to transport The Beast and the presidential vehicle fleet.  

There is no official confirmation that The Beast was onboard, as those logistics are a closely guarded secret. But US government vehicles have already been seen on the streets in Beijing.

The Secret Service is preparing a behemoth effort to protect Trump on his state visit to meet Chinese President Xi Jinping in Beijing.

The agency has been haunted by close calls since Trump's election campaign - and just last month faced further scrutiny when a gunman shot an agent while targeting the president at the White House Correspondents' Association Dinner in Washington. 

Security is complicated by the ongoing war with Iran, which shares close ties to China.

 Now several former Secret Service agents have lifted the lid on how the president will be protected abroad, and all the work that goes into it. 

'That whole package is flown in by the US Air Force,' former USSS agent Jeffrey James told the Daily Mail. 'Whether the president is going from Washington to Pittsburgh or all the way to China, the Air Force transports the limousines and armored vehicles for us.' 

The 22-year Secret Service veteran said the core of any presidential motorcade overseas is the so‑called 'secure package,' including The Beast, a backup limo, heavily armored follow cars and additional classified assets that travel with the president wherever he goes.

James described foreign motorcades as 'monsters' that are far more complex than anything stateside, adding that the transportation teams live and die on meticulous planning to keep all those vehicles moving safely in an unfamiliar environment.

'I've seen foreign motorcades reach 60 cars. Our secure package comes in, and then everything else, press vans, support cars, vehicles for the host delegation, gets rented locally.'

Multiple former agents told the Daily Mail that protecting the president in China may actually be easier than in many other countries, given Beijing's iron grip on public life.

'The government has a lot of control over the people over there,' ex-USSS agent Christian Bolf said. 'If someone were to run out in front of the motorcade in China, I'd be extremely surprised.'

He added that organized resistance was equally unlikely. 'I wouldn't expect any effort by groups in China to impede the president's visit. In some ways, going there makes things perhaps a little easier than some other countries.'

A second former agent, James, agreed, recalling a trip he made to China for the Service. 'One of the advantages of going to a country like China is that when they say they're going to clear the streets, they literally clear the streets,' he said. 'I remember motorcades where I didn't see a single person on the sidewalk.'

He was almost unsettled by how thoroughly Chinese authorities could sanitize a route. 'You literally don't see a soul,' he said.

On snipers, James explained that the US avoids placing local marksmen behind long-range rifles.

Instead, Chinese security officers are folded into the protective bubble as spotters, using their local knowledge to flag suspicious behavior while American snipers keep control of the guns.

Despite the thoroughness of those preparations, the Secret Service has been dogged by controversy since Trump's first assassination attempt in Butler, Pennsylvania.

The agency has suffered a string of embarrassments: in February, a 21-year-old breached Mar-a-Lago carrying a shotgun; in April, suspected gunman Cole Thomas Allen, 31, was found to have penetrated the White House Correspondents' Dinner.

On large foreign visits like this one, former agents said, the Service arrives weeks in advance to prepare and scout locations. 

So too does the White House advance team, whose job is to comb the host city for safe routes and secure buildings, working alongside Chinese counterparts to ensure the president can move smoothly between locations across Beijing.

'The US Secret Service works closely with the State Department and other US government partners to ensure a safe and secure visit,' a Secret Service spokesman told the Daily Mail. 

'Secret Service personnel arrive well in advance of the visit to work with our Chinese counterparts to ensure a safe environment where both delegations can work together.'

'The White House is fully prepared to ensure that President Trump's upcoming historic trip to China is not only safe but also productive,' White House spokesman Davis Ingle added.

One administration official was more candid about the finer details, saying the advance team is also responsible for ensuring 'a nice aesthetic' - the visit, they said, needs to 'look polished.'

All of it depends on a schedule that has yet to be made public. 

If there's a roundtable, the team ensures Trump gets a prominent seat; if there's a bilateral press conference, American flags will be positioned behind him; if there's a cultural visit, they will have already determined exactly where the press corps should stand for the best footage. 

As the host nation, China will submit its own preparations for White House sign-off - every detail, from backdrops to room layouts, negotiated and approved in Washington.

The logistics alone could occupy around 15 people for months.

Trump delayed the trip by six weeks, citing the Iran conflict as his reason for skipping the original late-March date. But both former agents said the regional tension would not compromise security. 

James noted that the protective apparatus around the president is specifically built to account for Iranian threats, along with those from other foreign actors and terror groups, including inside China.

'Anytime the president goes anywhere, we're always giving 100 percent,' Bolf said. 'The level of protection never drops.'