Developing missiles and selling the technology to countries such as Pakistan and Iran is one of the few ways he has been able to earn foreign exchange.

ECONOMIST: North Korea

When the windfall is exhausted, countries have to relearn how to earn their foreign exchange the hard way.

ECONOMIST: How to live with an overvalued currency

To earn the foreign exchange needed to pay for imports and to service debts, reliance on a single commodity (like Zambia's copper) is just too risky.

ECONOMIST: Zambian copper

The new sanctions make it a bit harder for the Kim regime to sell arms abroad and procure luxury goods for the ruling elite, but the regime will still be able to earn enough foreign exchange to import necessities for its Stalinist economy.

WSJ: Review & Outlook: Cutting Off the Kim Family Cash

And how long will Asian countries continue to spend money building up foreign-exchange reserves that earn next to nothing and carry the risk of currency losses, rather than use the money to invest in their own region, which seems set to grow an awful lot in coming years.

ECONOMIST: Buttonwood: Dollar dilemma | The

India allows 100% foreign ownership, but requires car companies to be foreign-exchange neutral - what they spend on imports must equal what they earn from exports.

CNN: INDIA'S CAR WARS