The U.N. is not alone in calling for such a move. Since the eruption of the global financial crisis last fall and the accompanying loss of confidence in the U.S. economy, Russia and China have each called for the creation of a global currency in order to facilitate a transition away from the dollar as the world's primary reserve currency.

Setting aside the economics of the debate, what is the political feasibility of these proposals? History may help to answer this question.

The idea of creating a global central bank that can print its own currency is not new. In fact, the idea has come in and out of vogue several times since World War II.

Perhaps the most famous attempt to create such an institution was led by Britain's influential, and now increasingly popular, economist John Maynard Keynes. As the Allies hammered out the post-war international economic order, Keynes proposed establishing an entity he called the "International Clearing Union" (ICU). This global central bank would serve as the primary depository of the world's international currency reserves. Rather than holding foreign exchange in domestic banks, states would pool their exchange in the ICU. Excess reserves would then be converted into bancors -- a reserve currency unit that would be used to settle interstate transactions, while remaining unavailable to the public. The bank would also be able to maintain a relative balance of trade between member states by penalizing excessive trade deficits and surpluses.

Keynes' proposal was flatly rejected by the American delegation, which preferred to seize the dollar's opportunity for a preeminent role in the post-war monetary order, and in any case was not keen on the idea of surrendering domestic control over monetary policy to a supranational entity.

Fast-forward two decades to the 1960s. No longer the world's leading creditor nation, the U.S. was instead facing a significant balance-of-payments deficit. This was, in part, just a natural consequence of the dollar's role as the international reserve currency. As the one currency that could settle any international account, the dollar was in demand, with states building up considerable reserves. But with the dollar backed by gold, fixed at $35 per ounce, the potential for a massive conversion of dollars to gold posed a greater threat. As a result, similar to today, the world faced a liquidity problem.

Renowned economist Robert Triffin began to lobby the U.S. government for the creation of a global central bank as the solution. Like Keynes' ICU, Triffin's plan had member nations depositing all foreign reserves in a centralized location. He nominated the International Monetary Fund (IMF) for this role. The IMF would then print its own currency, which would serve as the world's main reserve asset.

Triffin's proposal was also rejected by the U.S., which rather enjoyed the benefits of being the world's reserve center, among them the ability to cover large deficits by simply printing dollars. Were the U.S. to accept Triffin's proposal, it would be forced to finance deficits through its own reserves or borrowing from institutions like the IMF. Instead, the Federal Reserve pursued a number of band-aid policies until 1971, when President Richard Nixon made the monumental decision to take the dollar off the gold standard, ushering in the era of flexible exchange rates. Still, the dollar's central role remained intact.

So what are the chances the U.S. will embrace last week's UNCTAD proposal? Unlikely. The U.S. has twice passed on the opportunity to forego its "reserve center" status because it has consistently determined that the benefits of printing the world's reserve currency outweigh the costs. This logic holds even more for an Obama Administration that has largely funded its aggressive stimulus plan by printing dollars and selling American debt -- a strategy that would be impossible if the UNCTAD proposal were implemented. Despite early mixed signals, the Obama administration seems committed to defending the dollar's role.

Can the world just move forward without American support? Resoundingly, no. Any new global currency will not engender confidence if the world's biggest economy and the dollar are not behind it. Aside from the U.S., other major economic powers would have to be involved for the idea to get off the ground, which is far from a safe bet, either. Europe, for instance, is unlikely to subordinate the euro with its status continuing to rise.

So what is likely to happen? Change in the global monetary hierarchy, if it happens at all, will take place over several decades. The dollar may slowly lose its position as the world's premier currency asset as states seek to diversify their foreign reserves, thereby reducing exposure to potential swings in the dollar's value if the U.S. economy continues to decline. China is already moving in this direction. This is not to say the dollar's role in international finance will disappear, just that it will likely work in concert with a group of currencies likely to include the euro, yen, pound sterling, and perhaps, someday, the yuan.

For all the talk of a global central bank and matching currency, two of the 20th century's greatest economic minds -- Keynes and Triffin -- have already tried and failed. UNCTAD would have done well to brush up a bit on their economic history. That way, they might have drafted a proposal that at least has a chance of being adopted.

**Daniel McDowell is a graduate student at the University of Virginia currently pursuing a Ph.D. in foreign affairs.