By Christopher Harper

Marine Sgt. Steve Russell was on guard duty. It was Sunday, a day of rest.

As he gazed out of the compound’s gates in Beirut, he saw a truck turn and head for the Marine outpost.

Then a wave of flames swept across the truck’s bumper, sending tons of explosives in a suicide attack.

Amazingly, Russell survived. But the explosion killed 241 military personnel—almost all of them Marines, who had come as part of a peacekeeping mission after the 1982 Israeli invasion of Lebanon. It was the largest loss of life among the Marines since Iwo Jima in World War II.

A seminal event in the chaos of the Middle East, the bombing 40 years ago still provides some insight into what led to today’s events.

As an investigative journalist for ABC’s 20/20, I spent several months back then in an attempt to piece together who was behind the attack and why.

Here are the reports:

Here’s what we found:

–Iran financed the attack on the Marines to humiliate the U.S. government and its presence in Lebanon, particularly when the Reagan administration pushed for Arab countries to make peace with Israel.

–Syria, a longtime ally of the Islamic Republic and enemy of the United States and Israel, provided the logistical support for the operation.

–Islamic Jihad, a front organization with ties to Hezbollah, provided the manpower in Lebanon. Heading the operation was Imad Mughniyeh, one of the Middle East’s prolific terrorists and bomb makers. As a chief strategist of Hezbollah, the Lebanese Shia group, he deployed truck bombs and improvised explosive devices throughout the region, including the war in Iraq.

–The Reagan administration failed to recognize the danger the Marines faced in Beirut. For example, the guards protecting the compound were under strict orders to keep their guns without any rounds in the chamber to protect against civilian casualties. Moreover, the American military command failed to inform the Marines about the possibility of an imminent attack—information received a few days before the explosion.

–The Reagan administration largely ignored the attack’s impact on the Marines for two reasons. First, only days after the attack, the United States invaded Grenada to rescue American medical students. Second, a significant divide existed within the administration between those who wanted retaliation against the terrorists and those who argued that the government had no definitive proof of whether Iran and Syria were involved.

What can we learn about today’s issues from the past?

First, a clear connection has existed for decades among Iran, Syria, and the Palestinians. You don’t need a smoking gun to know that a link exists between the trio. Syria cannot play as prominent a role today because of its ongoing civil war.

Second, Hezbollah has become a powerful influence in the region, particularly as the leading party in the Lebanese government and an ally of Iran. Moreover, Hezbollah provides aid and assistance to Hamas, the main instigator of the attacks on Israel.

Third, Shia Muslims, the smaller of the two main branches of Islam, control a vast swath of the Middle East, including Lebanon, Syria, Iraq, and Iran. That’s a significant shift from the balance of power in the past 40 years when Sunni Muslims controlled much of the territory. That’s why Saudi Arabia leaders, who are from the dominant Sunni tribe, have started to talk with their longtime enemies from Iran.

Fourth, it’s important to note that the Sunni-Shia détente also includes the Palestinian leadership, which is primarily Sunni. Moreover, it’s important to note that the Palestinian political groups, which historically made no differentiation among Sunnis, Shia, and Christians, have created ties with distinctly religious regimes.  

Lastly, the United States has a history of putting itself in harm’s way in the Middle East, wagering that a show of military strength will somehow frighten its adversaries. So, too, has shuttle diplomacy played a role in the U.S. strategy.

Let’s take a good, hard look at how many failures the United States has had in the Middle East over the past four decades. Only the first Gulf War stands as a victory.

It may be time to sit this one out.