Addiction is chemical. Propensity for addiction is genetic/ biological. Willpower has very little to do with it. And keep in mind, on some level we’re all addicts. Endorphins trigger your opiate receptors. Anything you do for fun, anything that triggers that endorphins release, especially if you KNOW it’s going to, is, in the strictest sense, an addiction. And being a jerk seems to trigger Hitchens’ endorphins. So maybe he should use his willpower.
Addiction is chemical.
For many it is a habit, a behavior. behaviors are complex
Many drunks/druggies are not chemically addicted.
KCNK13 is a channel in the brain that is expressed differently in alcoholics.
There are others. Once there are therapies that address these things, I think addiction can be "cured" but it's very complicated.