Ignorance and stupidity are not interchangeable concepts.
Ignorance is about refusal or denial of facts regardless of the imperial evidence of the validity or veracity of the assertion of said facts.
Stupidity is about the fundamental lack of, or deficiency in, the ability or capacity to absorb or comprehend basic or elementary information.
Ignorant people don't want, or care, to know what they know they don't know.
We are constantly engaged in a war against both ignorance and stupidity.
If you're literate, you're in it whether you choose to be or not.
You're a foot soldier in the constant and continuous battle between enlightenment and ignorance, and the war between stupidity and intelligence.
Fight on! The battle isn't over.
Fight on! Let there be no retreat.
Fight on! The war's yet to be won.
Fight on! 'Til our victory Is complete.