How did their movement elude our recon satellites?
ff
I don't know that they did. As best as I recall, there were numerous news stories about the truck convoys going into Syria at that time. I don't know how they were spotted, but I suppose it had to be either by manned aircraft or by satellite.
After the all the attention given by the press to the fall of Baghdad those reports seemed to have been forgotten. But I well remember at the time there was lots of speculation by the ex-military "experts" on Fox about the convoys possibly moving WMD out of Iraq to storage sites in Syria.