This week marks the 20th anniversary of the deployment to Guam of one of America's most important and expensive weapon systems — the B-2 Spirit.

The B-2 was originally intended to carry nuclear bombs deep into Soviet territory if the Cold War had ever turned hot. Its shape — paired with the plane's stealth systems — would enable it to be undetected by Soviet radars. The B-2's long range meant it could fly deep into enemy territory and return home.

With the collapse of the Soviet Union and the end of the Cold War, the B-2 has been used as a conventional bomber. It made its combat debut during the Kosovo War in 1999, and has since flown sorties in Afghanistan, Iraq, and Libya.

More recently, the B-2 has been placed in bases in the Pacific as part of a strategy to deal with potential threats from North Korea.

Here's why it's one of the most feared aircraft in the world:

 

The B-2 bomber was shown to the public for the first time in 1988, just before the end of the Cold War. Its stealth capabilities were virtually unmatched.

The B-2 bomber was shown to the public for the first time in 1988, just before the end of the Cold War. Its stealth capabilities were virtually unmatched.
B2 Bomber at initial public rollout in Palmdale, California. Notice the the taxiway art work, using five B-2's to create a star, November, 22, 1988.
 Wikimedia commons

 

The B-2 can carry sixteen 2,400 lb B83 nuclear bombs, but its official limit of 40,000 lbs of ordinance means it can carry a massive amount of Precision-guided munitions.

The B-2 can carry sixteen 2,400 lb B83 nuclear bombs, but its official limit of 40,000 lbs of ordinance means it can carry a massive amount of Precision-guided munitions.
A B-2 drops 47 individual 500 lb (230 kg)-class Mark 82 bombs during a training exercise, 1994.
 Wikimedia commons
 

The B-2 has a max range of 6,900 miles on a single tank, but aerial refueling can keep the bomber up indefinitely.

The B-2 has a max range of 6,900 miles on a single tank, but aerial refueling can keep the bomber up indefinitely.
A B-2 Spirit flies into position during a refueling mission over the North Atlantic Ocean, June 11, 2014.
 US Air Force

 

On one bombing mission, two B-2s flew a 34-hour round-trip mission from Missouri to Libya, and were refueled in the air 15 times.

On one bombing mission, two B-2s flew a 34-hour round-trip mission from Missouri to Libya, and were refueled in the air 15 times.
A B-2 Spirit stealth bomber makes a fly-over at Soldier Field before the Green Bay Packers take on the Chicago Bears on September 13, 2015 in Chicago, Illinois.
 Jonathan Daniel/Getty Images
 

Each of the current 20 B-2s in service are named after a states. Here, the Spirit of New York can be seen at the British Royal International Air Tattoo in July of 2012.

Each of the current 20 B-2s in service are named after a states. Here, the Spirit of New York can be seen at the British Royal International Air Tattoo in July of 2012.
The "Spirit of New York," a B-2 Spirit at the Royal International Air Tattoo, July 2012.
Wikimedia commons

The B-2 is a flying wing aircraft, so it has no fuselage or tail. This means it has low drag, high structural efficiency, and generates more lift than other fixed-wing aircraft.

The B-2 is a flying wing aircraft, so it has no fuselage or tail. This means it has low drag, high structural efficiency, and generates more lift than other fixed-wing aircraft.
A U.S. Air Force B-2 Spirit stealth bomber flies overhead at the “Legacy of Liberty” open house and air show at Holloman Air Force Base, New Mexico, October 8, 2011.
 US Air Force
 

The B-2's max speed is Mach 0.95, or 630 mph.

The B-2's max speed is Mach 0.95, or 630 mph.
A U.S. Air Force B-2 Spirit Stealth Bomber takes off from Nellis Air Force Base, Nevada, June 1, 2017, as part of an afternoon training mission during the Weapons Instructor Course.
 US Air National Guard

Because of its capabilities, B-2s have been deployed to Guam to keep an eye on North Korea.

Because of its capabilities, B-2s have been deployed to Guam to keep an eye on North Korea.
Two U.S. Air Force B-2 Spirit aircraft deployed from Whiteman Air Force Base, Missouri, sit on the parkway prior to takeoff at Andersen Air Force Base, Guam, Jan. 12, 2017.
 US Air Force
 

They are also extremely important for keeping other countries like China and Russia in check.

They are also extremely important for keeping other countries like China and Russia in check.
An American Soldier salutes as a B-2 Spirit flys over prior to the NASCAR Sprint Cup Series Coca-Cola 600 at Charlotte Motor Speedway on May 29, 2011 in Concord, North Carolina.
 Chris Graythen/Getty Images

At home, the B-2 is often seen in flyovers during sports events.

At home, the B-2 is often seen in flyovers during sports events.Harry How/Getty Images
 

The B-2 is currently one of three strategic bombers currently in use by the US Air Force, the other two being the B-52 Stratofortress, and the B-1 Lancer. The Air Force plans to retire the B-2 in the early 2030s.

The B-2 is currently one of three strategic bombers currently in use by the US Air Force, the other two being the B-52 Stratofortress, and the B-1 Lancer. The Air Force plans to retire the B-2 in the early 2030s.
A B-1 Lancer, B-2 Spirit and B-52 Stratofortress perform a flyover during the 2017 Barksdale Air Force Base air show, May 6, 2017.
 US Air Force