历史上，白宫被称为“人民之家”，因为它的维护和保养是由纳税人支付的 - 总统只是一个“临时”居民。因此，已经做出努力使其看起来不像欧洲堡垒或皇家围墙化合物。
It only looks that way. What you’re not seeing are the layers of security.
Historically, The White House, has been referred to as “The People’s House” since its maintenance and upkeep is paid for by taxpayers — and the President is only a “temporary” resident. Because of this, efforts have been made to make it look less like a European fortress or a royal walled compound.
The layers of security start well away from the White House itself.
The airspace above and around the White House is restricted airspace. You’re not allowed to fly a plane in this zone without prior permission from air traffic controllers. Those controllers must obtain authorization from the U.S. Secret Service first. If you do violate that restriction, at the very least you’ll probably lose your pilot’s license and face federal charges. Ignore the ATC directives and you’ll find an F-15 Eagle or F-16 Falcon on your wing. For a faster response, though, the Secret Service has the capability to take down an incoming aircraft from the roof of the White House (though it’s more likely they’ll move the President instead).
Approaching in Washington D.C.
Another layer begins with cameras on all the streets around and leading to the White House. When you get near the grounds, you’ll notice it is surrounded by “wrought iron” fencing.
Look closely at the “spikes” on top of the fencing. They’re designed to discourage fence-hopping and do a good job of snagging clothing. But those vertical fence pieces aren’t iron, but high-strength steel, I’m told.
Oh, all those men on the White House lawn? They’re from the uniformed division of the Secret Service, examining the grounds after a drone flew over the fence and crashed on the lawn.
Access into the grounds is limited to security checkpoints like the one below. There are those bollards to block vehicle entry as well as tire deflating spikes in the pavement. It’s heavily monitored by Secret Service in at least two locations.
The grounds themselves are a layer of security. Hop a fence and you have to cover a lot of open ground. You’ll be seen. You’ll likely be intercepted. And those agents who intercept you are not known for having a sense of humor about intruders. Especially the furry ones.
Note the agent with the rifle is watching for any secondary intruder while his mates tend to the idiot who hopped the fence.
There are things you don’t see around the grounds. Motion sensors, infra-red sensors, night-vision/daylight cameras, infra-red laser detection grids, bulletproof glass and doors (inside & out). The Secret Service had an observation facility installed atop the building several years ago. It can be used to spot trouble and/or prevent unlawful entry attempts.
If you enter the White House, prepared to be screened much more thoroughly than what the TSA does. There are rules and protocols that require visitors to be screened before entry.
And all those Secret Service agents? There are offices for them in the building and they can quickly field an impressive array of ordnance if it becomes necessary. This includes the use of drones for surveillance as well as being equipped to jam signals to other drones.
The White House includes some rooms below the building, such as the Presidential Command Center. It’s rumored that these facilities were upgraded and expanded a few years ago, including fast elevators to get the first family out of harm’s way.