We are all ignorant about something in life. We live in a vastly complex world and it is impossible for us to have in depth knowledge on every subject. Not every one of us in this world can be a renaissance man. I for instance am vastly ignorant when it comes to flying planes. My knowledge goes as far as I get on one, and the guy in the cockpit fly's it. The difference between my ignorance and being stupid about flying a plane is that I willingly acknowledge that I do not know how to fly a plane and do not purport to have the knowledge to fly a plane or claim to know how to tell those that fly the plane how to do so. I let them maintain their expertise and yields to them in the area where they are subject matter experts.
Ignorance is when we have little or no knowledge on a given subject no matter how big or small. Stupid is when we ignore our ignorance and claim that our limited knowledge about a subject covers all that needs to be known to pass judgement on a subject. As has been said by others, "Ignorance is not terminal, stupidity is."
We are a world full of ignorant people. Our government has always been made up of ignorant people with the exception of a few well enlightened individuals scatter sparsely through out our countries history. The difference is that in previous times the majority of those that led us did not claim to know all. They were humble men who knew the limitation of their knowledge. What we have become or are in the process of becoming is a nation of stupid people. The people leading our nation see themselves as betters than the common man. Therefore they know more on any subject even those they know nothing about. This is what is getting us into major problems. How can you pass judgement on anything that you know nothing about and are unwilling to learn about. This is why we have statements such as we must pass it to know whats in it. Even if the leaders had read it, the content was too far out of their knowledge base to understand and they were too stupid to take the time to learn what they need to know to sit in judgement on whether it is good or not because they are better than the rest of us. They are too "Important" to take time to do so. They have better things to do.
The biggest problem our Nation faces today is that we choose to be led by the Stupid.
Their biggest problem is that when it comes to light that they lack knowledge on a subject they do not ask what they got themselves into, or go study to increase their knowledge. No, they make excuses and blame those that brought their ignorance to light for the problems. Oh, and trash those who know something about the subject as knuckle dragging neanderthals because who has time to learn about these things except backwards people who are crazy.
Now being "Ignant" (Ig-nun-t) that is a completely different conversation.