After reading that column, I hope mines are part of it. Do you recall whether the Iraq-Syria border is one of the places they found tunnels? I don't know much about mines, but I'll bet they could be "planted" in layers -- sort of like spring bulbs, at different depths, so that somebody tunneling would take the chance of running into one. As I said, though, I don't know much about mines.
I don't think that strategy alone works long-term. The Romans tried it in Germany.
Instead of a purely static defense, you need punitive retaliations to back it up.
Put up the border defenses in Iraq - after blasting Syria back to the stone age, and creating enough destruction Iran to prevent futher development of their nuclear program and allow any dissidents to drive out the ayatollahs and take over.
But don't bother to send in American troops or dollars to help put Syria back together again.
Let the Syrians rot until they evolve into humans.
Let the Iranian revolutionaries remove the current leaders and use Iran petroleum dollars to rebuild the destroyed infrastructure and, if they wish, provide them with financial and technical assistance.
The foregoing is the only solution to the immediate problem.
Then we can switch focus to the Wahhabists in Saudi Arabia and deal with them next.