Devils advocate: can't you just use that argument on anyone who doesnt agree with you about anything.
That is to say, you start with a thesis: tax is robbery. Then to back that thesis, you say that anyone who doesnt believe it has inattentional blindness. It would be just as easy for me to say
my dog is a cat. The preceeding statement is obvious. Therefore, if you don't think my dog is a cat, you must be experiencing inattentional blindness.
Also, the phenomenon youre describing seems to be limited to visual things. Failing to "see" that tax is robbery (failing to "see" the definition that is) isnt visual. Its just a turn of phrase.
Also, as a methphor it doesnt work. Because the thing you fail to see must be readily apparent. that is to say, if your inattentional blindness makes you blind to tax as theft, then the obvious thing must be that tax is theft not just that tax exists.
well I come at it from the standpoint that taxation fits the exact definition of robbery. It is robbery. There is no way to disagree with that. You can say it is "justified" but you can't get around the fact that it is still robbery. Most people however, simply don't see that is exactly what it is.