Why is 18 old enough to gamble with my life in Iraq but not old enough to gamble with my money in a Casino?

Why is 18 old enough to gamble with my life in Iraq but not old enough to gamble with my money in a Casino?Why can 16 year olds consent to sex when they can't even look at porn till 18? That doesn't make sense! Wouldn't you need more maturity for the real thing? Also 18 year olds are old enough to legally be adults but can't have a beer till 21? There are so many other dangerous things your allowed to do at 18 that far outweigh having a beer at 21. Who is making up these laws? What the hell were they thinking?