U.S. Air Force Secretary Michael Donley’s July 25 disclosure that the long-delayed 30,000-pound GBU-57B "bunker buster" bomb known as the Massive Ordnance Penetrator (MOP) could be used in action immediately if needed is probably an attempt by the Obama administration to signal to Iran that U.S. military action is on the table in the event that diplomacy and economic sanctions fail to convince Tehran to give up its nuclear program. The announcement is also probably another bid by the Obama administration to discourage a unilateral Israeli attack on Iran, as LIGNET explains.
Secretary Donley’s announcement was probably intended to reassure Israel and other U.S. allies in the region that the United States has both the will and the means to attack Iran's nuclear facilities if and when the time comes. However, U.S. allies and foes will probably be underwhelmed by Donley’s announcement because of the small number of these bombs and the difficulty of using them due to their enormous size and weight. Moreover, the development of this weapon has been known since 2006, which has given rogue states like Iran and North Korea plenty of time to improve the defenses of their WMD facilities.
With rogue regimes and terrorist groups increasingly moving their most dangerous weapons deep underground, the development of ground-penetrating “bunker buster” bombs has become a priority for the United States and its allies. The GPS-guided MOP is envisioned as the mother of all penetration weapons with a warhead carrying 5,300 pounds of high explosives. Iranian nuclear facilities, some of which are in hardened underground bunkers or built into the side of a mountain, are believed to be the primary potential targets of this weapon. Pentagon planners may also be looking at North Korean underground WMD facilities as possible targets.
In its current configuration, the MOP is believed capable of penetrating 60 feet of concrete. Ambassador John Bolton has stated that although he is unsure whether such weapons could destroy Iran’s deeply buried WMD facilities, he believes these powerful bombs would do so much damage to access tunnels and air shafts that it would render the facilities unusable for a long period of time.
If a single bomb could not destroy an underground facility, multiple bombs could be dropped on the same location, essentially using the weapon’s precision GPS system to dig a bigger hole. However, the GBU-57B is so large it reportedly can only be carried by either a B-52 or a B2 stealth bomber, and each plane can carry only two bombs. Each bomb costs $15 million and only 20 have been ordered.
Long flight times by multiple bombers may eliminate the element of surprise to drop these bombs on Iranian nuclear facilities and expose bombers to a greater risk from ground-to-air missiles believed to be defending these facilities.
Donley and Secretary of Defense Leon Panetta have both said that the GBU-57B will continue to undergo testing and development to make it even more effective.
“If it needed to go today, we would be ready to do that,” Donley told reporter Jeff Schogol of Stars and Stripes. “We continue to do testing on the bomb to refine its capabilities, and that is ongoing. We also have the capability to go with (the) existing configuration today.”
It is widely believed that Israel has developed its own bunker buster weapons, but they are thought to be expensive and less effective than the American-built variants and Israeli leaders have long wanted to acquire U.S.-built anti-bunker bombs. The Obama administration reportedly agreed in 2009 to sell 55 5,000-pound GBU-28 bunker buster bombs to Israel for possible use on the dug-in arsenals of Syria and Hezbollah in southern Lebanon.
The original Israeli request for bunker buster weapons came in 2005 and was initially approved by the Bush administration. Delivery was delayed by several years, however, after the Pentagon became suspicious of the possible diversion by Israel of advanced defense technology to China. U.S. officials also worried that providing the weapons to Israel might be giving it a green light to take unilateral military action against Iran, igniting a wider Middle East conflict.
While experts believe the GBU-28 would not be effective against several of Iran’s hardened and underground nuclear facilities, many of these facilities are above ground or are not deeply buried and could be extensively damaged by this weapon.
There were many press reports that Israeli Prime Minister Benjamin Netanyahu asked President Barack Obama for more bunker buster bombs when they met in Washington last March and that the president agreed to provide the weapons if Israel agreed to put off a possible attack on Iran until after the November 2012 U.S. presidential election. The White House denied these reports.
While there has been press speculation that Netanyahu asked Obama for GBU-57Bs, LIGNET believes this is unlikely since the United States has ordered so few of the bombs and Israel probably does not have a bomber large enough to carry them.
The announcement of the super-bunker buster bomb will affect the calculations by Iranian leaders on how to better hide and defend their nuclear program but will do little to convince them that a U.S. attack on Iranian nuclear facilities is more likely in the short term. LIGNET believes – and assesses that Iran believes – that there is zero chance that President Obama would order U.S. airstrikes on Iran unless it was in response to an Iranian attack because of enormous popular U.S. opposition.
Iranian leaders have thus far ignored increased economic sanctions and appear to have used the prospect of a possible unilateral Israeli airstrike to stretch out multilateral negotiations to make it politically difficult for Israel to attack. Unconcerned about a U.S attack in the short term, Tehran will probably continue such policies.
U.S. development of the GBU-57B has been public knowledge since 2006. Iran and North Korea have probably been working since that time to reinforce hardened WMD facilities and build them deeper into the earth with multiple underground entrances that could survive an attack by this new weapon.
Since Israel probably lacks a bomber large enough to transport the GBU-57B, the Obama administration may be using the prospect of a future U.S. attack on Iran using this weapon to discourage Israel from conducting a unilateral airstrike on Iran this year. LIGNET doubts such a strategy will work and believes that Israeli officials will decide on whether to attack Iranian nuclear facilities based on their own security considerations and what may be a rapidly closing attack window. LIGNET experts believe this window may close by the end of the summer and rate the chances of an Israeli attack at under 50 percent.
If the Obama administration believes the announcement of the 30,000 pound GBU-57B bunker buster will alter Iranian or North Korean WMD policies, it will be disappointed since neither state sees any possibility of a U.S. attack, at least as long as Barack Obama is president. The small number of these bombs also reduces the threat they pose to rogue state WMD facilities. Instead, Iran and North Korea have probably already taken steps in response to news of this bomb to better defend their WMD facilities and programs. The calculus of these states, especially by Iran, concerning this weapon would change should Mitt Romney win the presidential election this fall, although they likely believe that a new Republican administration would not take offensive action for a year or more, giving them more time to increase their defenses and hide WMD facilities.