The U.S. used the largest non-nuclear bomb it’s ever deployed in combat on April 13. The Massive Ordnance Air Blast bomb — nicknamed the Mother of All Bombs — was dropped over Islamic State positions in Afghanistan’s eastern Nangarhar Province. Here’s what we know about the weapon.
1. What’s this bomb?
The guided bomb unit GBU-43/B MOAB is a 21,600-pound weapon. It was released from an MC-130 transport plane by parachute and used Global Positioning System navigation to maneuver to its target, according to an Air Force statement.
2. How does it work?
The MOAB is an “air burst” weapon that explodes about six feet above the ground. This increases its destructive range because its energy isn’t directed into the earth. And it’s a thermobaric weapon, also known as a “vacuum bomb,” that sucks all the oxygen out of the surrounding air to set off the blast. This force can rupture lungs.
3. Why was it made?
The U.S. has long seen a need for weapons that clear a broad area all at once. The MOAB is a successor to the Vietnam-era, 15,000-pound “Daisy-Cutter” bomb used to clear trees from a 500-foot ground area so helicopters could land. That weapon was also used for mine-clearing in Afghanistan in 2001. The U.S. developed the BLU-118/B “Bunker Buster” in the early 2000s to penetrate underground targets. Its hard skin allowed it to go through more than six feet of concrete before it exploded. “Bunker Busters” were used on targets in Baghdad during the U.S. invasion of Iraq in 2003. The same engineer who designed the “Bunker Buster” designed the “Mother of All Bombs.”
4. Why was it used in Afghanistan?
White House press secretary Sean Spicer said the MOAB was dropped to reach “a system of tunnels and caves” used by Islamic State terrorists. The headquarters of U.S. forces in Afghanistan issued a statement saying that “the strike was designed to minimize the risk to Afghan and U.S. Forces conducting clearing operations” against Islamic State fighters and their facilities. The Air Force statement said that the weapon is designed to clear targets in caves and canyons, to clear extensive mine fields, and for “psychological effects.”
5. What psychological effects?
Military officials have said that the explosion of a MOAB feels like a nuclear blast, and a test of the bomb in 2003 produced a mushroom cloud visible 20 miles away.
6. Were the effects meant for anyone other than Islamic State?
U.S. President Donald Trump was asked whether the bomb’s use sent a message to North Korea, whose advancing nuclear weapons program he has vowed to stop. Trump replied that he didn’t know and “it doesn’t make any difference” because the problem of North Korea “will be taken care of.” But that didn’t stop speculation that the big boom in Afghanistan was meant at least in part as a warning to North Korea and Iran, which Trump accuses of seeking nuclear arms.
7. Could the GBU-43 be used against their nuclear sites?
To effectively strike the nuclear facilities that Iran and North Korea have built underground, the U.S. would have to use an even larger bomb, the Massive Ordinance Penetrator. It’s never been deployed in combat.
The Reference Shelf
- The U.S. Department of Defense released a video of the MOAB strike in the Nangarhar Province in eastern Afghanistan.
- A U.S. Air Force article describing the MOAB and its first test in 2003.
- The 2005 New York Time obituary for Albert L. Weimorts, a civilian engineer who designed the “Bunker Buster” bomb and the MOAB.
- A Bloomberg QuickTake on the war in Afghanistan.