16:05 Sep 7, 2010 

"Career soldier" suggests to me someone who makes a career of soldiering, with the ambition of rising through the ranks, to the best of his ability. It could be synonymous with "professional soldier", though a "professional soldier" might envisage soldiering only as a temporary occupation rather than a career, "until something better comes along". A "professional lance-corporal" would be a professional/career soldier currently with the rank of lance-corporal. A "career lance-corporal" could well be a professional soldier with no chance or ambition of ever rising above that rank but intent on pursueing his career in the army.