Our general rule of thumb regarding radios and communications equipment... Zero it out if it's going to fall into the hands of the enemy (there's a button for that.) If you don't have time to zero it out, we were also provided an axe to smash the radio if need be. (If current or future crypto, changed weekly, fell into enemy hands-- they could listen to our communications.) Obviously smashing it to bits with an axe is a last resort measure, but... It was a measure.