The United States once played a key role in keeping the peace between Taiwan under the Kuomintang and Mao Zedong’s China. Now, it’s in danger of setting both sides on a dangerously confrontational path. Since cross-strait relations are highly complicated, let’s just consider a single aspect: the so-called median line in the strait. The line is not as well-known as the air defence identification zone (ADIZ), which is usually self-proclaimed by a governing state rather than being recognised internationally. So the US could violate China’s ADIZ while China could breach Taiwan’s ADIZ without too much repercussion. Such moves may be provocative, but not necessarily escalatory, as in leading to a potential military confrontation. The median line is a different matter. While also informal and has no status in international law, it has been respected by both sides, at least until recently. As Beijing has vowed to respond forcefully to any visit to Taiwan by the speaker of the US House of Representatives, Nancy Pelosi, we will likely be hearing more about the median line in the coming days or weeks. More Chinese warplanes could be crossing the line and staying longer on the Taiwan side as a show of force and displeasure. Washington helped broker the line in 1954 after the end of the Korean war, which diverted Mao’s military attention away from the Kuomintang and invading Taiwan. In retrospect, China today might have been better off if Mao had gone ahead with an invasion of the island rather than committing to North Korea. This may be one of history’s great what-ifs, but it is likely there would have been a unified China and a unified Korea, resulting in far fewer flashpoints in the Asia-Pacific. Planes, ships and missile tests: how Beijing might react to Pelosi’s Taiwan trip But, in any case, the median line held for decades. However, Beijing openly repudiated the unofficial demarcation line in September 2020. That month, dozens of Chinese warplanes crossed over it for two days in retaliation at visits made by two cabinet secretaries under the administration of Donald Trump. Even so, since that crisis, China has been reluctant to cross the line that it no longer acknowledged. However, in June, Beijing declared the Taiwan Strait was not “international waters”. That was in response to increasingly frequent transits by the US Navy. Since 2020, such provocations – at least as China has characterised them – have averaged one a month. So far this year, there have been at least six naval transits. So, what does escalation mean? Early last month, several PLA fighter jets crossed the median line on the Taiwanese side. Last week, perhaps in retaliation, a large number of US fighters breached the median line proposed by Tokyo between Japan and China. We can easily see how a flashpoint south of the East China Sea may easily extend to its north, blowing up into a regional conflict. China will progressively disregard Taiwan’s ADIZ and even the median line, effectively rendering them as non-existent. Likewise, it will do the same with the island’s maritime exclusive economic zone and may even challenge its actual territorial waters; God forbid. For the life of me, I can’t see how Pelosi’s grandstanding helps Taiwan’s security or that of the region other than further inflaming an already dangerous situation.