YES

There is no law (or enforcement) on drug use in international waters. The problem is that such a ship would be unable to dock or sail in a prohibitionist territory.

Also, a legal source of cannabis would have to be secured.

Even more troublesome would be the fact that no prohibitionist nation would grant the cruise company a business license. No bank based in a prohibitionist nation would be able to grant a loan either.

From my perspective it appears the entire thing would have to be Netherlands based.

Not a bad idea though if there are any “budding” entrepreneurs.