Whatever excuse they use, US House of Representatives Speaker Kevin McCarthy's planned meeting with Taiwan regional leader Tsai Ing-wen on Wednesday will deal irreparable damage to their national credit as well as a heavy blow to the Sino-US relationship.

It was solemnly written in the three Sino-US joint communiques that "there is only one China and Taiwan is part of China", which has been recognized by every US president and repeated every time the two nations' leaders met since.

Now, by allowing Tsai's "stopover" in US territory and arranging for a political leader to meet her, the US government is ruining its own national credibility.

The notice that McCarthy will host a bipartisan meeting with Tsai further shows a consensus is being formed in the US political sector. An "anti-China" cloud is forming over Washington, made up of the dust of the Cold War, which will surely plummet the Sino-US relationship to a new low.

But Tsai needs to know rather than an honored guest, she is a just a geopolitical chess piece.

When then-Taiwan leader Lee Teng-hui "stopped over" in Hawaii in 1994, he was reportedly given a small room to rest without being allowed to step on US soil. What the US is doing this time is anything but a routine practice as they claimed, which only serves as further provocation.

It is an escalation they will dearly pay for.