He said it had something to do with Vietnamese religious beliefs ... something about not being able to "move on" without your noggin. Don't have a bloody clue whether that was accurate or not, but he did say that wherever these South Korean tanks went, it was like the parting of the Red Sea ... armed resistance just melted away until they left the area. Of course, the NVA and Viet Cong didn't want to engage any massed armor units, as a general matter ... not good odds for them at all.

The essential American soul is hard, isolate, stoic, and a killer. It has never yet melted. ~ D.H. Lawrence