Originally Posted by plaster

Not sure why it would have to be precast panels. Form it up and pour it, pretty simple stuff. If 1000 miles at 12 billion... that's 12 million a mile, or $2,272 a foot. A nine foot wall is estimated at around $80 per foot... what makes you think a 35 foot wall would cost $4,000 per foot? Because someone said so? 3 foot base tapered to 1 foot at the top. Nobody is cutting 3 foot solid concrete.

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For sake of argument... the wall would need to have some type of sensor for when they try to scale it. That would certainly cost money. And surveyors and engineering costs money. But I just can't see how it would end up anywhere close to $4,000 per linear foot (close to 25 billion dollar mark) for everything including dirt roads being created.