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what impact can we make professionally in 15 years though? :)

What kind of impact do we need except earning/saving money :)

Military personnel and employees with beneficial careers in the security sectors (police, firemen) have that luck.
But thay need to save their life...
One of my friends (a friend from elementary school) is retiring these days. He shortened his working life by 15, 16 years by working for the army. But I'm sure he will continue to work in the private sector.

Most I know have continued on in private.