Ignorance is curable, being simply a lack of education. All of us are ignorant, about different things. Many on the left are ignorant about guns (as I've notoriously said before), I think in large part due to their primary exposure being popular culture, TV and movies that have been feeding them twaddle since birth. Some are completely ignorant of how financial markets work (me), or the fine details of how electronics work. Whatever the area of ignorance, it can be eliminated by simply acquiring information.
Willful ignorance is a horse of an entirely different color. Intentionally ignoring information on a subject in order to maintain a death grip on an ideological position can't be solved with information the ignorant person will not take in. When their entire worldview absolutely depends on maintaining a fiction, anything that upsets that fiction is unacceptable, and is automatically rejected, regardless of fact.
Creationists are, in my opinion, the foremost proponents of willful ignorance in American society.
The evidence for evolution, largely in accordance with ol' Chuck Darwin's theory, is overwhelming and irrefutable, as is the evidence of the age of the Earth, give or take a hundred million years here or there. The problem is when you wrap your entire existence around a fairy tale that is completely undermined by those simple facts. You either accept the evidence, deny it says what it says or you make elaborate rationalizations to try to make the evidence fit the fairy tale, or the fairy tale fit the evidence.
I need not list all the damage done throughout history, including recently and ongoing, by those who are not willing to relinquish their grip on their fairy tale, or its grip on them; if you happen to be ignorant of this history, just learn it.
There is another group of willfully ignorant folks, currently doing damage to generations who aren't here yet, the climate change deniers. The motivation for this bunch is, at root, almost entirely economic. Companies and individuals profiting from the current system, and not worried about something twenty or fifty years off when they have a quarterly report due in a month, have financed the creation or fostering of a wide variety of willfully ignorant groups, from those who reflexively oppose anything supported by their supposed enemy (how many thousands still won't even consider anthropomorphic climate change simply because Al Gore loudly blew the whistle?) to those led around by the nose by "leaders" bought lock, stock and barrel by corporations.
Then there's those whose fairy tale is threatened by climate change science.
And now new research by Yale's Dan Kahan further reaffirms that there's something going on here. More specifically, Kahan showed that there is a correlation (.25, which is weak to modest, but significant) between a person's religiosity and his or her tendency to think that global warming isn't much of a risk. Perhaps even more tellingly, Kahan also found that among highly religious individuals, as their ability to comprehend science increases, so does their denial of the risk posed by global warming.
Why Climate Change Skeptics and Evolution Deniers Joined Forces
There is a chilling video in that piece.
I don't have a solution to offer, or anything particularly profound to say. Just found it interesting.