I do believe that our work does not define us......but what we bring to our work that defines us.
You can be the greatest person in your organization, but you may not bring any of your real self to your work - just your super training and intellect...cold and clinical alone does not ever work...
Or, you could have chosen to be a motorcycle mechanic, but you bring your passion for things mechanical, your love for life, and your very real personality to your work, and in so doing make your workplace happier and brighter...
There are times when circumstances force us to take up any job that comes along - no matter--give it all you've got - you define it - and you'll see the transformation (I've been in this situation, and since I came upon this truth through a lot of heartache and trouble, I know it works--and works beautifully).
If you have the chance to choose something, don't-don't-don't-ever-ever-ever make the mistake of believing that your job position defines you - NEVER - you have to define it. If it is a corner store that makes you happy, go for it.....and do not believe anyone who goes - how could you, with all your qualifications do this? or how could you do this, with no thought of your family prestige? or how could you give up so much to do this for a pittance? or have you no thought for what you can contribute to the world (coolly forgetting that even the humblest - in man-made-terms - contributes to the world going round). If you know you have it in you to change policies, then hit the top of the ladder - but bring your self to it, and define it in your terms.
You have to make your life, and make it as happy as possible - and bring yourself to what you put your hand to, or have to put your hand to, or choose to put your hand to...