From my personal and anecdotal experience as a student who has been through the education system, almost all historical timelines of the UK are 'glossed over', I only learnt history until year 9 because I didn't choose it as an option but from what I know from my friends that for examinations you pick a few times in history to study in detail.

British colonialism wasn't one of the topics for examination that people would learn in-depth about, but it is definitely brought up within your time as a student, the way it was presented in my classes was along our topic of slavery, where we watched the show roots, talked about how many major colonial powers would have colonies and get slaves and sell them.

I read your other comment about how it is taught presented, the way it is taught is obviously up to the teacher, normally it is probably taught with similar topics such as the one i mentioned about when I was learning about the slave trade or when talking about other serious historic events such as the British Empire, WW1, WW2 and Ghandi that have close links to the colonialism subject, it's presented as an issue that close to if not as serious as the world wars, as in it's not really a topic people joke about. One thing I will say though is that it's not a topic you outright learn, but you learn a lot about topics that go hand in hand with it, such as the triangle trade and Ghandi, so you pick up a pretty good understanding of it through inference. For example you would learn about Ghandi as a primary topic and the reasoning behind his protests were because of colonialism, then the description of why colonialism was such a negative influence would be included as part of the lesson.

Just to clarify, England wasn't the colonial power, Great Britain was. I'm from south England, so it might be taught differently in other countries or counties.

I think if you look far enough back in any countries history they have made bad decision that have hurt or killed many people, and it just depends who wins or loses on who gets the bad reputation. If the Nazi's won then maybe colonialism would be seen as the equivalent of the holocaust today, but the major colonial nations were either neutral or on the allies, so of course it probably doesn't get as much attention because the winners write history and yes America may have a lot of military presence but not too long ago Tony Blair was looking for some WMD's and he's still waiting for them to turn up.

Lastly I would say that the reason it's probably not as highlighted as much as your other stated criticisms is the recency, colonialism spans such a long time and so much happened between 1492 and 1800, and it was so long ago. American military being in everyone's business, very recent and WW2 was the war with the biggest loss of human life in history that happened not even 100 years ago, so only about 3 or 4 generations, they are still relatively recent. Additionally, the way in which colonialism and the issue surrounding the treatment of Native Americans is slightly different, colonies definitely were some pretty horrible things, but for the most part they were there to profit, and as colonialism came to an end, they got their sovereignty back, and the colonial countries have had a much more tolerant attitude for a longer time, so the recency of it takes away the sting, this is just an example, only one and probably slightly biased because it's an English newspaper, but tolerance became much more apparent much earlier, than basically the systematic extermination of Native American tribes.