How Do These Arms Have Such Legs?

This quote is appearing over and over in coverage of our latest offensive against terrorist 'strongholds' in Iraq: "Pentagon officials concede that al-Zarqawi's men are better equipped and better trained than previously believed."

I don't understand. Better equipped? By whom? How? Better trained? By whom? Where? How?

All of this is extremely disturbing. It seems to indicate that there are depths to this situation that have never been fully revealed to us as citizens. Is there a chance that this 'insurgency' can continue to grow without the backing of any official state? I feel that we NEED TO KNOW more than we are being told.