Countries with trade surpluses benefit from trade because they use the unspent foreign currency to invest in their prosperous trading partner.

FORBES: Is 95% of the Trade Imbalance Legal Tax Evasion?

"We're getting back to an environment where investors can trade on fundamentals rather than rhetoric, " said Nigel Khakoo, co-head of foreign-exchange trading in Europe at Nomura in London.

WSJ: Strong Start to 2013 Hints at Revival for Currency Funds