Aftermath
Investigation
After the blast, an assessment crew consisting of the Central Intelligence Agency (CIA), Federal Bureau of Investigation (FBI), Diplomatic Security Service (DSS), and U.S. Air Force investigators was dispersed to assess the risk to other security compounds in Saudi Arabia, and to offer suggestions for the Khobar Towers complex. It was suggested that Mylar tape be used to coat the windows for a barrier, but the cost, about $4.5 million, was considered prohibitive. It was also suggested that the perimeter be expanded to at least 500 feet to save servicemen from flying glass.
Intelligence and security failures
After the bombing of Khobar Towers, the U.S. military and intelligence community came under heavy criticism for their lack of preparation and foresight for what was considered an intelligence failure. According to the New York Times, "significant shortcomings in planning, intelligence, and basic security left American forces in Saudi Arabia vulnerable."
Numerous warnings had been made available to the intelligence community and military command, and up to "ten incidences [were] reported suggesting that the Khobar Towers are under surveillance" from April to June, 1996. These warnings came both before and after the beheadings of 4 Saudi nationals after their publicly confessed role in the November 1995 attacks in Riyadh. Clinton Administration officials admit that they "received a wave of threats against Americans and American installations in Saudi Arabia" in the weeks leading up to the attack, "but failed to prepare adequately for a bomb of the power that killed 19 American military personnel." Threats were also downplayed by the Saudis when Defense Minister Prince Sultan bin Abd al-Aziz al-Saud characterized acts carried out by Saudi Islamic Jihadists in 1995 as "boyish," and stated that the Saudi "Kingdom is not influenced by threats". Senator Arlen Specter (R-PA) commented during a Senate intelligence committee meeting by saying "there was no intelligence failure ... there had been more than 100 intelligence reports on alerts of a general nature, and very specific reports" of an extant and present threat to the Khobar Towers complex.
The CIA was blamed for misjudging the bomb-making capabilities of Saudi militants, arbitrarily deciding that no bomb could exceed the size of that used in the November 1995 bombings in Riyadh (200 lbs). According to official U.S. government estimates, the Khobar bomb weighed in at approximately 5,000 pounds. American commanders were also blamed, as they had not taken every precaution advised by the Pentagon; specifically, because "the project was deemed too costly," they had failed to implement a recommendation to coat Khobar's windows with plastic to prevent shrapnel penetration.
The main security concern at the Khobar Towers compound before the bombing had been the prevention of an attack similar to the 1983 Beirut barracks bombings, when a vehicle-bomb enter the compound itself. Yet the Pentagon's report from that incident suggested, as did the Khobar report, that a Beirut-sized bomb would still have caused significant damage from as far as 300 feet away. Officials concluded with the observation that bomb size was less important to the production of catastrophic results than that same bomb's effective proximity (blast radius).
Operational relocation
As a result of the terrorist attack, U.S. and Coalition military operations at Khobar and Dhahran were subsequently relocated to Prince Sultan Air Base, a remote and highly secure Royal Saudi Air Force installation near Al-Kharj in central Saudi Arabia, approximately 70 miles from Riyadh. American, British, and French military operations would continue at Prince Sultan until late 2003, when French forces withdrew and American and British operations shifted to Al Udeid Air Base in Qatar.
Culpability
Initial blame
The bombing of Khobar Towers, according to the Saudi government, was carried out by "Saudi Islamic militants, including many veterans of the Afghan War." One U.S. official claimed that "it now seems it was not an isolated case. There is an organization of violent opponents whose members are loosely connected, organized in semi-independent cells like other violent fundamentalist movements in the Arab World."
Indictment
The three-year investigation had led the FBI to conclude that Iran was involved in the attack. At that time, the Clinton administration hoped to open a dialogue with reformist president Khatami, which would be impossible after accusing Iranians of supporting terrorist action. A secret letter, delivered directly to Khatami by Sultan Qaboos of Oman, stated that the United States had evidence of direct Iranian involvement in the act, and demanded that those involved be held responsible for their actions. Khatami refused to begin an investigation and Iranian officials stated that al-Qaeda was responsible for the attack.
In April 1997, the Chairman of the Joint Chiefs of Staff, Gen. John Shalikashvili, said that the Pentagon did not have sufficient evidence about the bombers to consider retaliation against foreign countries that may have played a role.
In June 2001, an indictment was issued in United States District Court for the Eastern District of Virginia in Alexandria, Virginia charging the following people with murder, conspiracy, and other charges related to the bombing:
Ahmed Ibrahim Al-Mughassil
Abdelkarim Hussein Mohamed Al-Nasser
Ali Saed Bin Ali El-Hoorie
Ibrahim Salih Mohammed Al-Yacoub
Hani al-Sayegh (Who had been previously in U.S. custody but deported to Saudi Arabia, when charges against him were dropped due to a lack of evidence.)
Eight other Saudis
One Lebanese man listed as "John Doe".
In July 2001, Saudi Arabia said that eleven of the people indicted in the US were in custody in Saudi prisons, and were to be tried in Saudi court, as the country refused to extradite any of them to the United States to stand trial. The government has not since made public the outcome of the trial or the whereabouts of the prisoners.
In August 2015, Arab newspaper Asharq Al-Awsat reported that Ahmed Ibrahim Al-Mughassil, a leader of the militant group Hezbollah Al-Hejaz found to be responsible for the bombing, had been arrested in Beirut and transferred to Saudi Arabian custody; an anonymous American intelligence official told The New York Times that the Saudi government had not confirmed the arrest, but U.S. intelligence believed the report was accurate.
Attribution to al-Qaeda
Abdel Bari Atwan wrote:
In May 1996 Bin Laden and his entourage moved from Sudan to Afghanistan. As if to make the point that they might have been chased out of Sudan by Saudi Arabia and the US they were not leaving with their tails between their legs, al Qaeda struck again: The June bombing of Khobar Towers. The Saudi authorities were at pains to implicate Shi'i militants backed by Iran in this attack, since the embarrassing truth that they had their very own homegrown militancy problem was inadmissible; they did not want to give the impression that there was domestic opposition to the deployment of US troops on Saudi soil.
In 2004, the 9/11 Commission noted that Osama Bin Laden was seen being congratulated on the day of the Khobar attack, and stated there were reports in the months preceding the attack that Bin Laden was seeking to facilitate a shipment of explosives to Saudi Arabia. According to the United States, classified evidence suggests that the government of Iran was the key sponsor of the incident, and several high-ranking members of their military may have been involved. A U.S. federal court speculated that the Khobar Towers bombing was authorized by Ali Khamenei, the Supreme Leader of Iran.
William Perry, who was the United States Secretary of Defense at the time that this bombing happened, said in an interview in June 2007 that "he now believes al-Qaida rather than Iran was behind a 1996 truck bombing at an American military base."
On December 22, 2006, federal judge Royce C. Lamberth ruled that Iran and Hezbollah were responsible for the attack, stating that the leading experts on Hezbollah presented "overwhelming" evidence of the group's involvement and that six captured Hezbollah members detailed the role of Iranian officials in providing money, plans, and maps. This decision was reached as a default judgment, however, in which the Iranian government was not represented in court, and had no opportunity to challenge the allegations.