Drunk driving is not contagious.

In addition, drunk driving is a relatively controlled problem. That is, a relatively small percentage of the population do it and law enforcement is able to police it with a reasonable degree of success. On the other hand, it we had an epidemic of drunk driving where say 20% of the people on the road were driving drunk then it very well may make sense for the government to barricade the roads until they got things under control.

You argue that allowing free commerce on the highways is okay with a relatively small percentage of the population being dangerous to others.

And yet you argue that allowing free commerce in America is not okay with a population that is dangerous to a relatively small percentage of the population.

Different amount of percentages. You're not killing 1% of your population and permanently disabling another 10% every year to support free commerce.

In three months we've permanently disabled 10% of the populace? Where did you read that?

I don't think you realize how common drunk driving in in rural areas. 20% of the people on the road after 6-7 pm could be drunk in certain areas.

Edit: Found this as a support source, while not 20% roughly 2x the rate in rural vs urban areas https://www.ncbi.nlm.nih.gov/pubmed/30160320

that doesn't change the fact that you cant "catch" being drunk by being in the vicinity of someone who didn't know they were drunk.

You've not been to wild parties, I guess.