I have been in the U.S. for over 40 years. I was not born here butI served in the army when I was about 19 years old and was discharged under honerable conditions. Am I automatically a citizen because I served in the army ?

No, joining the army does not really give you any privileges. It depends on where you were born, when your parents naturalized or obtained permanent resident status, etc. After the year 2004, if you returned from the war and you were already a permanent resident, you can apply for citizenship in one year.. no need to wait for 5 years.