If you're going to worry about that, wouldn't you be more concerned about the operator being fully blind? And simply justify not hiring the vision impaired for

If you're going to worry about that, wouldn't you be more concerned about the operator being fully blind? And simply justify not hiring the vision impaired for this particular position? "safety-critical systems with a large user base" Surely a missile warning system would be operated by a very, very small number of people, on the order of twenty or thirty?