The point in the Bible about defiling one's self and dirtying up the temple of the body is what COMES OUT OF THE MOUTH, BECAUSE WHAT GOES IN IS A-OKAY.
The point of not becoming a SLAVE to addictive substances is to not become addicted to it so that it becomes number one in one's life, thereby crowding out time for more important things.
That means that hookah and pot should be okay as long as one doesn't become addicted to them, which is a little difficult to do for a lot of people.
Pot may become legal later, so at that time it won't be violating U.S. law (caesars became extinct a long time ago, so I don't use that term anymore).