Would a doctor classify it as alcoholism to have a beer a night?

One beer?: No, not one beer per day, unless it's a very large beer. Usually, one will not experience any alcohol withdrawal symptoms without drinking at least 4-8 beverage alcohol equivalents for every day for one month. A beverage alcohol equivalent means one 12 ounce beer, one 4 ounce glass of wine or one shot of liquor. Alcoholism has to do with how impactful the alcohol has on impairment of functioning.

Depends: Not all high risk drinking is alcoholism. According to the national institutes of health, high risk drinking in men is more than 4 standard drinks in a given day (1 standard drink = drink containing amount of alcohol in 12 oz. Of regular beer), and more than 14 drinks/week, and high risk drinking in women is more than 2 standard drinks in any given day and more than 7 standard drinks/week.