As the November mid-term elections in the United States approach, the Democrats and the Republicans have both found a new villain to run against. "China emerges as a scapegoat in campaign ads," as The New York Times recently put it.

The China blame game is taking place amid escalating trade tensions. As the US puts pressure on China to allow its currency to increase in value, the rising euro and yen have led the European Union (EU) and Japan to join the chorus. The charges are not new, but the tone has escalated steadily since early summer, when the prospects of the Democrats' loss in the mid-term elections became evident.

Due to economic stagnation, political polarization and unemployment in the advanced world, the yuan has become a convenient scapegoat. Yet the very concept of "currency manipulation" is flawed. Today, all governments take measures that affect the exchange rates directly or indirectly.

The debate over "currency manipulation" moved to a new level in September, when the US House of Representatives approved legislation that would allow the US to seek trade sanctions against China and other countries for "engaging in currency manipulation" to gain trade advantages.

However, cheap imports from China have not been the primary cause for the decline of manufacturing output or job losses in the US. Even a significant exchange adjustment would not bring the lost low-cost jobs back to the US. Instead of importing low-cost products from East Asia, US consumers would just buy them from Vietnam, Bangladesh or Sri Lanka.

Had China been the primary cause for the US trade deficit, China would have accounted for it. In reality, when the US trade deficit peaked in 2007-08, China contributed a third of the deficit, while Japan, Russia and oil-producing countries accounted for the rest.

Last year, China's current account surplus was 6.1 percent of GDP, whereas Saudi Arabia's amounted to 11.5 percent. In Germany and Japan, the comparable figures were 6.6 percent and 5 percent. Yet neither Saudi Arabia nor Germany nor Japan has been accused of currency manipulation.

Right before the euro crisis in spring, the US enjoyed the benefits of the strong euro. By the logic of "currency manipulation", the EU should have accused the US of manipulating the exchange rate to boost exports at the expense of the euro zone.

When George W. Bush was the US president, the White House supported free trade but stood for unilateralism in security. In contrast, the Barack Obama administration has supported multilateral security policies but has been flirting with unilateralism in trade. Consequently, a series of currency frictions have been sparked worldwide because global rebalancing has failed.