It was cloudy in Dallas the morning of Nov. 22, 1963. The Secret Service thought they would have to put the transparent roof on the president's limo to keep the rain out.
"In the end, the sun came out, the sky cleared and they didn't use it," says Matt Anderson, curator of transportation at the Henry Ford Museum in Dearborn, Mich., which has that limo, and three other limos built for U.S. presidents, on display. "But the top in and of itself wouldn't have protected against a bullet."
It cost more than $200,000 (U.S.), the equivalent of $1.5-million today, to turn the sleek 1961 Lincoln into a car fit for John F. Kennedy, Anderson says. The White House didn't have that kind of budget, so it leased it from Ford for $500 a year. Add-ons included three different roofs, flashing red lights and running boards for secret service agents – but no protection from bullets.
"It wasn't originally armoured, it got sent to Hess & Eisenhardt in Cincinnati, where they stretched it by three-and-a-half-feet to make it look more presidential," Anderson says.
The car, codenamed the X-100, had a hydraulically operated backseat to lift the president by 10 inches for maximum visibility.
"Kennedy loved interacting with crowds – there are pictures of people walking right up to that car," Anderson says.
After Dallas, the president's car became a fortress on wheels. Since George W. Bush's term, the cars are custom built from the ground up – it's speculated that they're built on truck platforms. They have to be to handle the weight of the armour.
"Everything changed after Dallas – security became more important than visibility," says Gregg Merksamer, who's written about presidential limos for the New York Times and Popular Mechanics. "The cliché was that it was a more innocent time, maybe that's true. JFK was the fourth president assassinated, you'd think they would have been a little more circumspect."
Presidents Franklin D. Roosevelt, after Pearl Harbour, and Harry S. Truman, after a 1950 assassination attempt, had limos refitted with armour – but it wasn't the norm. While Roosevelt's 1939 Lincoln convertible was being retro-fitted with bullet-resistant glass, steel plating and a compartment for machine guns, he rode in an armoured 1929 Cadillac that had been confiscated from Al Capone.
"Keep in mind, all the way back to President [William Howard] Taft, who had a white steamer, none of these leaders rode in closed cars – they wanted to be as visible as possible," says Tom McPherson, a Toronto-based expert on presidential limousines. "They wanted cars that were built to reflect an image, of power and prestige – now, a world leader would have to be insane to do what Kennedy did."
The X-100 was the last convertible for a U.S. president – and the last vehicle built without armour.
After the assassination, it was decided that it would be faster and cheaper to rebuild the Kennedy car instead of starting from scratch. It was cleaned out and sent back to Hess & Eisenhardt for Project Quick Fix. About $500,000 (about $3.5-million today) was spent to add titanium plating, bullet-resistant glass windows and a roof, run-flat tires, a protected gas tank, and filters in the heating and cooling systems to keep out poison gas. The floor plating was tested to resist eight sticks of dynamite.
The Kennedy car was used until Jimmy Carter's term in 1977 – Lyndon B. Johnson had it sent back to get a rear window that could be opened, and Richard Nixon added a sunroof so he could stand to wave at crowds.
"That wouldn't happen now, that's how poor Benazir Bhutto was killed in 2007," Merksamer says. "There are people out there looking to test vulnerabilities – when they get revealed, they get corrected."
The last car with opening panels in the roof was the 1972 Lincoln limousine, retired during Ronald Reagan's presidency.
"It's the last car we know the weight of – 13,000 pounds," Merksamer says, "That car helped shield President [Gerald] Ford from Sara Jane Moore's 1975 assassination attempt in San Francisco and it took a .22-calibre Devastator bullet in a right side when John Hinckley shot President Reagan in 1981."
Details of the president's ride, even retired versions, are a secret – the Secret Service didn't include the keys with the Clinton limo now at the William J. Clinton Presidential Library and Museum in Little Rock, Ark., and nobody there is allowed to see the inside workings.
"The government claims these cars are impregnable," McPherson says. "That's an irresponsible statement because you can never be 100 per cent sure."
McPherson says little is known of the details of cars used by Canadian prime ministers, but today all cars used by the PM are armoured. "The first one I know of is a limo built for Pierre Trudeau in 1972," McPherson says.
The RCMP was asked for details of the prime minster's past or current cars – including the two sent to India in 2011 for the Prime Minister's visit last year – but there was no response. The Secret Service was also asked for details on the current presidential car, dubbed The Beast, or previous cars.
"It's not a secret, we just don't talk about it," says Secret Service spokesman Brian Leary.
What's different in these cars today? For the president's vehicle, newer materials such as Kevlar, carbon fibre and ceramic may have made each car slightly lighter than its predecessor, at least up until the current car, McPherson says.
Based on photos, Merksamer guesses that President Barack Obama's car probably has five inches worth of ballistic armour under its skin, weighs four tonnes and is probably based on a modified Escalade platform. It's an armoured truck with a car's skin. The laminated glass probably weighs more than the metal used for armour, he says.
"It's all speculation – maybe three or four people know exactly what it's designed to do," Merksamer says. "There's no such thing as bullet-proof, the armour's a catcher's mitt for bullets and not a trampoline – bullets don't bounce off, this isn't Knight Rider."
He guesses it's sealed against chemical attack, and that the president's compartment can only be opened by a button from the inside.
As for reports by the Daily Mail that the car can fire machine-gun bullets, launch tear gas canisters and carries a supply of the president's blood: "All that James Bond stuff about the tear gas dispensers and Obama's blood in the trunk is fanciful thinking at its silliest," he says.
"If there's anything unusual in the trunk of that car, it's communications gear, because job one when the president is riding around is that he should be able to get in touch with anyone, anytime, from NORAD on down to your great-grandma celebrating her 100th birthday."
The car itself isn't the only level of protection – Merksamer says its now surrounded by other protected vehicles and secret service agents – and the car always travels with at least one identical decoy.
"Were there an attack, the Secret Service detail would likely rely on quick, accurate fire from their own hand weapons, anything up to military assault rifles but nothing bigger), and they certainly wouldn't keep the president around while they shoot it out," he says. "The objective always is to get the president out of the danger zone."
While most world leaders – and an increasing number of embassy staff – are asking for better protection, Pope Francis hasn't been using the armoured Popemobile that became the norm after John Paul II was shot in 1981.
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