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.