You have to ask Obama whats the use of "10% sanctions with exemptions" ? Iran is mostly self-sufficient in food items, only few imported items like cars, gadgets etc are affected. Also has over $100 billion in cash reserves in tax-havens & gold bullion, which is enough for few years. A total naval & land blockade may have been more effective, but not such eye-wash sanctions. And since many countries are co-operating with Iran in thwarting the sanctions, they are clearly not effective.
Suspect Bangkok bomber arrested, found with possible bomb-making materials (Reuters)