I was stationed at Grissom AFB, and I know there are high barbed wire fences and lights, but they weren't designed to keep people IN. I've been on Ft Benjamin Harrison, and spent time in the camp for exercises. I don't remember large amounts of concertina wire. If there had been, I'd remember it since I likely would have had some close, personal contact with it. There were nests of rattlesnakes.

When you aren't familiar with a place, whether a fence points in or out depends on what someone tells you AND whether you believe them. I'm fairly suspicious of anything someone tries to get me to believe, no matter which side it's coming from. For instance, "FEMA detention facility". What's the difference between a detention facility and a refugee camp? The answer is that the true difference is in how it's used, when it's used.

As for why there are so many FEMA facilities, they plan where to set up camps if local or regional disasters occur.

There isn't open land anywhere in the US that couldn't be turn into a detention camp with concertina wire and armed guards. There isn't a military facility or kids' camp that couldn't be easily adapted. This concentration camp page is intended to feed off paranoia and boost the membership of anti-government militia groups. It's also somewhat of a diversion from things that are more provable, even if they don't seem quite so evil.