Your "proper answer" is what the US tried to do in Iraq, which is now considered the perhaps biggest mistake in US history.

Iraq is in the running for the biggest mistake in US history? I have a one word rebuttal to that sentence. Slavery.

I'm sure we can find a lot of things more horrible than Iraq. Like slavery as you say, or bombing Hiroshima and Nagasaki, or the war in Vietnam...

But what I think OP meant, is that the bad things which happened in Iraq were not the intended outcome of what the US did. Those other, more horrible things were intended consequences, not mistakes.

I'll agree that slavery was worse than the invasion of Iraq, but I wouldn't call it a "mistake".

Not quite sure why. Some tries:

1. A mistake implies a single decision.

2. Slavery worked as intended, right? It was more evil than mistaken.

Either way, you sure derailed my derailing of the topic, so I'll stop here :)

Calling slavery a mistake is very... mild. It should have its own category

I think mistake implies good intentions.

Also, it's very strange that you can imply The United States started a war with good intentions with a straight face.

I always think of mistake as simply "to be wrong". Am I mistaken in my assumption?

Kind of, yes. If you're wrong intentionally, we have all sorts of other words for that, including trolling, propaganda, misdirection, incitement, lying, fraud, perjury, all of which have their own connotations for your intent. We wouldn't really call any of those situations a "mistake".

Not only did we try, but we did it the wrong way imo. When you try to pull something this complex off and completely disregard the local culture, politics, and sectarian makeup, you introduce chaos. Did anyone learn from Sykes-Picot?

Sorry but this is a very poor answer. Lack of understanding of the local culture is very evident. Every country in the world cannot have a system like the United states. Cleaning up the system without understanding it would be terrible. Just like Iraq!

Has it ever worked in that order? It seems like most current democratic countries first cleaned up the country and then introduced a democratic government. I’m thinking of recent democratic countries in Asia, like South Korea, Taiwan, and Singapore.

Or if they did start with a democratic government, to limit the voting to certain groups, like the US, Canada, and Australia did before universal suffrage.

Are there any successful countries that haven’t “cleaned up” first but introduced universal democracy?

Rulers derive power from other people. Your first job is to keep the people keeping you in power happy. Fail that, and you'll be replaced by someone else.

Democracy means shifting it from a small number of people keeping you in power to all of the people. It's not easy.

CGPGray did a great video on this model: https://www.youtube.com/watch?v=rStL7niR7gs (Based on The Dictators Handbook by Bruce Bueno de Mesquita and Alastair Smith.

The reason Russia loved Putin is because he cleaned up low level violence and corruption. It's hard to have democracy when people are getting shot in the streets. This is something you completely fail to understand. Furthermore, it's hard to have a "democratic government" when everyone is poor. This is so glaringly obvious that it's painful reading your post.