Hi,
I think that the question comes with the following options:
- different constitutions
- different elections processes
- absolute power or limited power
- family dynasties or tribal dynasties
Now, their monarchies are both absolute and without a constitution ( this would be rather modern European monarchies), and there are no elections- power is inherited.
which means that the main difference is that they are either family dynasties (Iraq) or tribal dynasties (Arabia).
