Talk to these kind experianced folks here on the IMF and they will tell you, ask them about the sacrfices you will have to make to live that lifestyle, ask them about the changes you will have to go through to achieve it, and maybe even the difference between the private sector and standard Uniformed Service.
I am sure they can iterate more clearly what I am talking about.
And this is by no means me trying to be confrontational, but I am saying this in a very honest sense, you should really really check all your convictions and your "reasons", it's easy say "I'ma gonna be a PMC" when you are 17...
Try and study the industry, everything from the lawsuits to the moral debates, most importantly get a list of your "reasons" and try and find and talk to those who have been there.
Sadly I will openly state that my generalized advice ends at that point, I cannot nor shall not claim experiance in these fields.
But lastly, look in the mirror, and ask yourself if you are willing to deal with the changes that can come with a career in such a field.