The US Foreign Affairs Committee of the House of Representatives on Wednesday passed a bipartisan measure to reaffirm the "Six Assurances" to Taiwan, the guidelines used in conducting relations between the US and Taiwan, right before the Democratic Progressive Party (DPP) comes to office.

The "Six Assurances" were put forward by former US President Ronald Reagan with the purpose of consolidating US support to Taiwan. Under the guidelines, the US would not set a date for ending arms sales to Taiwan, would not revise the Taiwan Relations Act, would not hold prior consultations with the Chinese mainland regarding arms sales to Taiwan, would not play a mediation role between the mainland and Taiwan, would not pressure Taiwan to enter into negotiations with the mainland and would not formally recognize the mainland's sovereignty over Taiwan.

It is not a big deal for the committee to reiterate the six promises. But it is silly if the DPP makes a big fuss of it.

The geopolitical context of the Taiwan question has profoundly changed compared with the Reagan era. The Six Assurances are not as significant as before. It even has become an obscure political term, which reflects its real value.

In 1982, Taiwan could link its fate to relations with the US more. But today, the mainland exerts a bigger influence on Taiwan's future than the US. Any statement, be it made by the Foreign Affairs Committee, the Pentagon or the White House, is unlikely to become a decisive factor of the Taiwan question anymore.

US arms sales to Taiwan are unable to affect the balance of power across the Straits as they did 30 years ago. Now the deal acts more as a link between the US and Taiwan, plus the US arms dealers can make money from it.

Washington could be more actively using the Taiwan card to deal with the mainland after Tsai Ing-wen takes office. That will cause tensions in Sino-US relations, but can never mean a turning point of Taiwan independence.

Taiwan independence is doomed to fail. This has become more certain now than eight years ago when Ma Ying-jeou came to power. There is a narrowing gap between China and the US in terms of national strength, and the balance of power between the two within the first island chain of the West Pacific has changed. The Taiwan question now is a "domestic affair" in its true sense.

Under modern military technology, the Taiwan Straits cannot serve as a defensive shield any more. The US has been always confident about the odds of military intervention anywhere in Asia, but it has to calculate carefully when it comes to the Taiwan question.

Besides military uncertainties, US intervention within the first island chain also has great global strategic risks. A tumble here will implicate its global hegemony.

Washington understands it cannot afford to challenge China's core interests, and therefore it does not want pro-Taiwan Independence forces to cross the red line.