What is the truth behind "foreign fighters" in Iraq?

Video Shows Foreign Fighters in Major Iraq Attacks

Foreign Muslim militants from across the Arab world have appeared in a chilling video tape which claimed they carried out some of the bloodiest bombings in Iraq since the war ended.......

The video shows several young Muslim militants uttering their final words before carrying out major operations such as last year's massive truck bomb attack on United Nations headquarters in Baghdad that killed 22 people.

It was the worst attack on a U.N. civilian complex in the organization's history....

The video showed Italian Prime Minister Silvio Berlusconi with his face sunk in his hands after last year's car bombing killed 19 Italians and nine Iraqis in the city of Nassiriya.

It said an Egyptian identified as Abu Fareed who had lived in Italy carried out the bombing after killing Christians in Egypt first.

Yesterday's USA Today is convinced they're practically non-existent.

Suspected foreign fighters account for less than 2% of the 5,700 captives being held as security threats in Iraq, a strong indication that Iraqis are largely responsible for the stubborn insurgency.....

The figures also suggest that Iraq isn't as big a magnet for foreign terrorists as some administration critics have asserted.

I would think that if foreign fighters are the ones blowing up the most people and the locals are responsible for some small arms fire, I would concentrate on the foreign fighters.