If the barricade's that good, how about fitting it with ports through which employees can get behind and answer incoming fire in like manner?
I always have my CCW on my person, even in my office here in S. TX. When I’m working near the border, I take my Mini 14. I even have a pistol on my desk at my office. Lots of folks down here don’t like us. Had a Mexican in a pickup try to run me down on my Harley a couple of years ago in Corpus Christi.