What if China is designated as a currency manipulator?

Mitt Romney has stated his position that, if elected as president of the United States, on his first day in office he would designate China as a currency manipulator.

That sounds tempting because currently, many domestic companies suffer due to cheap Chinese imports.  However, as in chess, that will not be the last move.   If that occurs and tariffs are placed on Chinese goods, allowing U.S. companies to more fairly compete, the Chinese will almost certainly place tariffs on goods U.S. companies are trying to export to China.    As the second largest economy in the world, this would have major negative consequences on both sides once a trade war begins.    The question will need to be asked, are the downsides of not designating China a currency manipulator lesser or greater than to designate China a currency manipulator?      Scenarios would have to be gamed out and domestic politics should be taken out of the equation.

The politicians know that if U.S. companies begin to severely suffer, it will be tied back to the designation of currency manipulation as the trigger.    Even if politicians confuse the issue with double talk, companies that suffer economically will be highlighted and the subject cannot be evaded.