Sen. Joe Lieberman writes:
[D]efeating al Qaeda in Iraq requires not only that we continue pressing the offensive against its leadership and infrastructure inside the country. We must also aggressively target its links to "global" al Qaeda and close off the routes its foreign fighters are using to get into Iraq.
Recently declassified American intelligence reveals just how much al Qaeda in Iraq is dependent for its survival on the support it receives from the broader, global al Qaeda network, and how most of that support flows into Iraq through one country -- Syria. Al Qaeda in Iraq is sustained by a transnational network of facilitators and human smugglers, who replenish its supply of suicide bombers -- approximately 60 to 80 Islamist extremists, recruited every month from across the Middle East, North Africa and Europe, and sent to meet their al Qaeda handlers in Syria, from where they are taken to Iraq to blow themselves up to kill countless others.
Although small in number, these foreign fighters are a vital strategic asset to al Qaeda in Iraq, providing it with the essential human ammunition it needs to conduct high-visibility, mass-casualty suicide bombings, such as we saw last week in northern Iraq. In fact, the U.S. military estimates that between 80% and 90% of suicide attacks in Iraq are perpetrated by foreign fighters, making them the deadliest weapon in al Qaeda's war arsenal. Without them, al Qaeda in Iraq would be critically, perhaps even fatally, weakened.