The essay prompt does not beat around the bush. It clearly tells you with the first sentence that it is not as interested in your past laurels, as it is in your future aspirations. So, while it is okay to give a couple of sentences of context, do not go into detail about your career path and achievements. The first part of the question should ideally be an extension of the previous goals question where you explain your goals in more detail – outlining your plan to get to your short term goal, what skill set you already have and what skills you plan to develop to enable you to be successful.
It is interesting to note that Columbia changed the second part of this question last year and shifted the focus from “how the Columbia MBA will help you achieve them” to “what, in your imagination, would be your long-term dream job”. The fact that they have retained the dream job part this year suggests that the ad com received what they were looking for in the last year’s applications. What has changed though is the concrete word limit of 500 words, instead of the open-ended word count suggestion of 100-750 words which highlights the need to be straightforward and succinct.
Don’t let the “dream job” wording take you away from practicality and reality. Columbia still wants to see where you will realistically land up in long-term and though these goals can definitely be lofty and ambitious, you do not need to make it sound fancy just for the sake of the essay. Also ensure that there is a good connect between what you plan for in the short term and what you aspire for in the long term. The admissions committee does not expect you to stick to your long-term or even your short-term plans to the letter, but they want to see that you have the vision to create and go for that plan.
Since 500 words is a lot to discuss just your career plans, it may help to mention how you arrived at these goals, the research you have indulged in etc. Also, if you would like to show some flexibility on your short-term goals, it’s completely ok to mention your Plan B (in the short term) as long as you connect it well with the same long-term goal mentioned. Since the next question expects you to talk more about Columbia in the context of being in New York, it may be a good idea to invest 70-80 words presenting opportunities at Columbia that you really connect with in the context of your short term or long-term goals.