We at OP have long suspected this to be the case.
More foreign fighters than ever are crossing Iraq's porous borders to fight U.S. and Iraqi forces, and a growing number are from U.S.-ally Saudi Arabia, a Senate Democrat said Thursday.
"The mix is changing," said Sen. Joseph Biden, D-Del., citing conversations last week in Iraq with Marine and Army generals. "Now, the mix is increasingly more Islamist crossing the border ... and a lot of them are Saudis. It presents a different profile" that is harder for U.S. forces to confront.
In the past, the U.S. military has said foreign fighters are a small percentage - perhaps one in 10 - of the insurgents fighting the U.S. presence in Iraq. They do a disproportionate amount of killing, however, in part because they are more likely to carry out suicide bombings.
One concept keeps coming to mind....."It's better to fight the SOBs over there then on our soil". Make no mistake, we are going to have to fight them eventually. May as well be now and there then later and here.