BEIJING - In the last of three rounds of US presidential debate, both candidates framed China as a partner for the first time, offering a speck of belated comfort as the country had been portrayed as a monetary cheat and a job thief in their previous face-offs.

In Tuesday's finale, the two candidates began to show a bit of companionship by stopping short of vilifying China 100 percent, as Barack Obama admitted, "China is both an adversary but also a potential partner," and Mitt Romney, fond of bashing China, said, "We can be a partner with China. We don't have to be an adversary in any way, shape or form".

A few relieving words, however, are quickly overshadowed by traditional campaign tricks of scapegoating and ill-grounded hypotheses. The US president-in-waiting, no matter who is elected, lacks deep understanding of how partners should treat each other.

The two candidates are still competing to flex their muscles on China. Romney repeated his threat to designate China a currency manipulator and punish it for intellectual property theft, while Obama continued to parade his "trophy" achievements while in office: doubling US exports to China, the most advantageous exchange rates to American business since 1993, and a special task force focusing on trade.

They have relentlessly blamed China to cover up their own inabilities to put the domestic economy on track, regardless of the truth. The tactic only serves to reveal that the world's superpower, indeed or temporarily,  is running out of ways to sort out the real problems.

Bashing China is a much easier and more convenient foil to score political gains.

The presidential debate, unsurprisingly, has fallen into a vanity fair for China-bashers who compete to denigrate China, which in fact has little to do with China but everything to do with the losing competitiveness of the world's superpower.

Both candidates vowed to "make China feel pressured to play by rules." But they should know that rules have never been built upon pressure, but candid talks and concessions taking mutual benefits into account.

Rules are not only important to America, but also to China itself. Even Obama himself acknowledges China's changes in exchange rates, that the yuan has appreciated by at least 31 percent since 2005, and US exports to China have doubled during his tenure.

A more balanced currency regime not only serves to balance trade, but also helps restructure and update China's exports, a development that is in the interests of the Asian nation.

While amending its behavior, China needs to stick to its own course and will not surrender to its bottom line. Appreciation by more than one third has generated positive results both in China and the United States. However, going further down that path will run counter to China's fundamental economic interests, a movement which will be blocked by the Chinese government and Chinese people without hesitation.

As the world's sole superpower, the United States is the main architect of global rules in arenas ranging from trade to military. It can file cases to the World Trade Organization whenever it finds the situation escaping its control. It can also block emerging Chinese companies with the excuse of threatening national security based on groundless accusations.

One thing that Obama should bear in mind is never to use out-of-context results to defend his record in addressing trade with China. He said tariffs against Chinese tires created US jobs, but he omitted other chain effects which are not that pleasant: US consumers paid 1.1 billion US dollars more for tires because of the move, according to a report released by the Peterson Institute for International Economics.

Meanwhile, although US tire imports from China declined by nearly 23.6 percent in 2010 from 2009, overall imports jumped by more than 20.2 percent, a fact that does not exactly bode well for American jobs.

Romney, who has been unusually truculent toward China, seemingly decided his stance in the first two debates was too aggressive, toning things down a little in the final round and dismissing suggestions that he would start a trade war with China.

It seems, fortunately, that the China-bashing game has not spun out of control, as the billionaire who used to profit handsomely from doing business with China knows that the largest and second-largest economies in the world, trade between which equals nearly a half-trillion dollars, could not afford the backlash of tit-for-tat tariffs and eventually all-out economic war.

Romney stated, "We can be a partner with China. We can work with them, collaborate with them if they're willing to be responsible." He should be reminded that partners must be responsible for each other.

The presidential candidates should also be mindful of going too far on bashing China, if they have to do so to win votes, since the specificity of their promise leaves them few options but to follow through.

But they are strongly expected to wriggle out of their tough promises on China between election and inauguration. If so, why bother to waste time and resources to fire away?