Originally Posted by
Distilled
And to address the first surprise, in the US after exiting customs and immigration you are always entering an area outside security, and have to go through security again. That is not an issue that AA has any control over. It's just that way at all airports in the US.
At IAD pax using the mid-field immigrations area get released from Customs directly to a TSA checkpoint and into the domestic terminal. This is the only path to follow using the mid-field Immigrations facility. Other pax arrive landside like at other airports.