I've never smoked hookah so I don't know exactly how strong it is personally. From what I know of it, in terms of creating a buzz or getting high, it's much weaker than weed and maybe stronger than nicotine.. maybe, except nicotine nowadays is a lot more dangerous and addictive because of all the added chemicals. Hookah is 100% legal. They even have hookah bars here in the states.
I only smoke cigarettes. Been doing that over 50 years. So I'll likely continue that till they lay me to rest.