Men like Mr Rogers don't crave power, though. To quote Douglas Adams:

“The major problem—one of the major problems, for there are several—one of the many major problems with governing people is that of whom you get to do it; or rather of who manages to get people to let them do it to them. To summarize: it is a well-known fact that those people who most want to rule people are, ipso facto, those least suited to do it. To summarize the summary: anyone who is capable of getting themselves made President should on no account be allowed to do the job.”

With equal (ie unlimited) access to both Ketamine is going to be a lot faster. They will both cause psychosis eventually, and both cause irreversible harm to major organs (kidneys/bladder and pancreas) after sustained use, but alcohol takes between 10-20 years of solid abuse before it starts to do serious damage, Ketamine only takes months to a few years.