If we simply look at the definition of: Abuse
ABUSE: use or apply improperly or to excess (this according to Webster), apply any substance or behavior and the concept of abusing something is quite clear. Alcohol consumed before operating an auto is applying it improperly, consumed in excess in any situation such that one loses control is likewise abuse. I agree with Sugah, abuse can be practiced by most anyone if the consumption and circumstance fall within the definition.
An alcoholic, in my opinion is someone like me that perfected abuse and turned it into "typical or routine behavior." In keeping with sugErspun's observations that a long term heavy drinker need not be an alcoholic, I suppose that is possible, although in my case I drank very heavily for some 25 years, but many simply excused my drinking as just that HEAVY DRINKING since I had all the stuff materially, ran my business profitably, and never had any legal issues. When was I an "official alcoholic?" I have always claimed I WAS NOT AN ALCOHOLIC UNTIL I WENT TO MY FIRST MEETING OF AA, but I most certainly had been drinking alcoholically for years.
As we like to say in AA "only you know if you are an alcoholic", however if alcohol is interfering with your life then it is my opinion that you have earned the right to walk into a meeting.
One final word on abuse, I always felt that was when one puts ice in 25 year old single malt scotch.
Just this man's opinion,
Jon