ACE Checkzone: The Confrontation Zone double-click video to start, click to pause. This video takes the vantage point of a soldier off the road watching cars approach the Confrontation Zone. Depending on the amount of traffic, one could imagine a larger operation to increase throughput. The yellow barricades divide the road into two lanes. The far lane (used by the black car as it pulls away) leads beyond the Enforcement Zone, so vehicles with a high certainty of being non-agressive are allowed to continue. In cases where the perceived risk is great (due to sensor readings and historical infmation) such as with the ambulance, vehicles are directed to the inner lane where they proceed under close watch to the Enforcement Zone. Videos require Quicktime. Narrative Traffic through the area is modest this afternoon. Most vehicles arriving into the Confrontation Zone have been analyzed prior to reaching the kiosk. From this information, soldiers can direct their questions to vehicle occupants regarding weight and distribution. An average of 5-10% of vehicles are directed to enter Zone 3, while most are allowed to continue. At one point an ambulance enters the zone and stops at the kiosk. The driver looks anxious, and the lights and siren are both flashing. The driver says he is in a hurry and must get to the hospital because there are two men in the back who have been seriously injured by gunfire. Readings confirm that this same vehicle 4 hours earlier was seen, with a different driver, carrying no passengers, at another location 10 miles away. Now, the vehicle is 650lbs heavier and is detected to be carrying large amounts of ammonium nitrate. Infra-red scanning reveals that there are indeed 2 people in the back of the ambulance, however their condition cannot be evaluated. The soldier makes the decision to send this vehicle into Zone 3 instead of allowing it to continue. Part of operating in adversarial environments is understanding that your adversary will continue adapting to your adaptations, and the enemy you're facing now is not the same enemy you faced 2 months or even 2 weeks ago. The following depictions illustrate that point. After a month or two of operating the Confrontation Zone, incidents of VBIEDs and other attacks beyond the checkpoint began to escalate again. It was discovered that the enemy began using a multi-vehicle strategy where they would send one vehicle expecting it to be stopped and searched, while in communication with another vehicle. The other vehicle would be 100-200 meters away and take advantage of the information being passed to them or simply use the distraction of the first vehicle to slip by uncontested. In response to this, soldiers working the checkzone began listening to foreign radio transmissions that originated from and were being sent to vehicles in the checking area. This method was an effective adaptation to the behavior exhibited by the enemy at the time. Future plans call for the ability to concurrently monitor activity in all 3 areas of the checkzone to better recognize enemy cooperative strategies.