Concertina wire is an area denial weapon designed to cause casualties and disable enemy elements that attempt to make their way through. It is often times used in conjunction with land mines, and preset ambush points set with inter-locking fields of fire. The area denial defense is suited for repelling well armed enemy forces.
Are un-armed refugees seeking asylum enemy ground forces? Should we force women with small children back into the river? Should we start killing each other to keep the nation safe from the world's poor? Did God tell us to murder people that are not like us? I think we all need to back off, take a breath and answer these questions. In the meantime, if you find immigrants to be repellant to your moral code you can back that up with other, non- violent actions such as refraining from golf and eating out, raising your own children and cutting your own grass.
Rand O
Not Captain Ron. Dr. Spaceman.