The world's most dangerous terrorist
Probing threats inside and out
By Henry Schuster
Editor's Note: Henry Schuster, a senior producer in CNN's Investigative Unit, has been covering terrorism for more than a decade. Each week in "Tracking Terror," he reports on the people and organizations driving international and domestic terrorism and efforts to combat those. He is the author of the forthcoming book, "Hunting Eric Rudolph."
Bin Laden, right, was a top U.S. target before 9/11, while al-Zarqawi more recently emerged as a major threat.
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(CNN) -- Abu Musab al-Zarqawi pledges allegiance to Osama bin Laden. Bin Laden gives his blessing to al-Zarqawi. So which man is the most dangerous terrorist in the world?
This question seems as good a way as any to welcome you to Tracking Terror. I've been covering terrorism for CNN for more than a decade, and this weekly space will be aimed at reporting, analyzing and even provoking discussion on issues of terrorism and security.
Which brings us to the issue at hand.
There seems little doubt that if there were a ranking of most dangerous terrorists, these two men would be at the top. But who is more dangerous?
In many ways bin Laden and al-Zarqawi represent two different types of threat.
The two men have a past together in Afghanistan, but no one is quite sure what it is.
But what matters most is that during the past 18 months, bin Laden has been repeatedly calling for an uprising in Iraq, while al-Zarqawi has been on the ground, carrying out a series of bloody attacks, from suicide car bombings to beheadings.
When al-Zarqawi made the first move towards bin Laden last year, sending him letters asking for bin Laden's blessing and said his group was ready to offer its support. There was silence from bin Laden.
Then a couple of months ago, al-Zarqawi's group changed its name, started calling itself al Qaeda in Mesopotamia. In a message a few weeks later, bin Laden offered his blessing to al-Zarqawi.
Arguably, bin Laden had no choice. While al-Zarqawi has been waging his campaign of terror in Iraq, bin Laden's threat as an operational terrorist ended with 9/11 and the subsequent U.S. invasion of Afghanistan. As the White House keeps saying, bin Laden is on the run and that diminishes his ability to carry out attacks. Losing a number of lieutenants, most notably Khalid Shaikh Mohammed (who planned 9/11), has also been a blow.
Al-Zarqawi has been busy, trying to make himself the leader of the insurgency in Iraq, and not being shy about it. He puts out his own audio tapes over the Internet, in the style of bin Laden, and most chillingly he claimed to be the man behind the mask executing American Nicholas Berg.
If you used death tolls as a measure, then bin Laden is ahead. September 11, the embassy bombings and a number of other attacks mean bin Laden has been directly responsible for at least 3,500 deaths.
Al-Zarqawi is closing the gap. Quickly and bloodily. He's still far behind, but not through lack of trying in places like Baghdad, Karbala and Najaf. It is just that his targets are smaller. But there are a lot more of them, and they have been much more recent.
Al-Zarqawi is primarily operational. Bin Laden is primarily inspirational.
Being on the run hasn't shut bin Laden up. To the contrary. He's put out about 30 messages since September 11. And there is little doubt that as a symbol, he has turned al Qaeda into something more akin to a movement than a simple terrorist organization.
Paul Eedle, a British journalist who has been following both men's careers on the Internet, puts it this way: Al-Zarqawi is in danger of imploding America's entire Middle East strategy. Bin Laden has the ability to catalyze new conflicts, making himself the leader of a worldwide movement.
"I don't think Zarqawi is going to join the dots. You can define his boundaries."
Eedle says as potent a symbol as bin Laden has become, he remains more than that. "Bin Laden is still capable of doing the unthinkable...such as trying to recruit Ukranians with fissile material."
Two very dangerous men. One a threat in a specific place where the stakes are extremely high. The other a symbol and a leader of a more transnational movement.
As I asked at the beginning, who is more dangerous? What do you think? Send your thoughts to trackingterror@CNN.com.