Quite simply, a US military intervention over Taiwan would violate international law
- Just as the US military shooting of China’s civilian balloon violated UN principles against the use of force, any military intervention in a conflict across the Taiwan Strait would make America an aggressor on Chinese soil
What legal basis does the US have, under international law, to intervene militarily in a cross-strait conflict? To answer this, we need to examine the reasons for a possible US military intervention.
The critical issue is whether these three categories of argument hold water under international law. This, as reflected in the UN Charter and international custom, only prescribes two scenarios for the legitimate use of force: UN Security Council authorisation or the right of self-defence. None of the three US categories of defence falls into either of the two scenarios for the legitimate right to use force.
Neither protecting democracy nor implementing domestic law is a lawful exception to the general prohibition against the use of force. If they were, any country could freely use force by claiming to be protecting democracy or through the enactment of a domestic law.
Although those two words are different in English, there is only one word for both in Chinese – qin lue (侵略). This is a weighty word and people tend to equate it with aggression.
But the term “aggression” has a specific meaning in international law, whether in the resolution on the “definition of aggression” adopted by the UN General Assembly on December 14, 1974, or in the amendment to the Rome Statute on the crime of aggression, adopted by the member states of the International Criminal Court on June 12, 2010. The determination of an act of aggression and the crime of aggression are strictly regulated.
In accordance with the provisions of the two international instruments, an “act of aggression” refers to the use of force by a state against the sovereignty, territorial integrity or political independence of another state or in any other manner contrary to the UN charter.
How could that be taken as an act of aggression under international law? If the US were to intervene militarily, it would be the aggressor, violating the UN’s fundamental principle against the use of force in international relations, in invading Chinese territory.
This has not only led to questions about the moral integrity of the West, but has also destroyed the collective security system enshrined in the UN Charter, which was designed “to save succeeding generations from the scourge of war, which twice in our lifetime has brought untold sorrow to mankind”.
This states, and we hope the US takes note, that: “All members shall refrain in their international relations from the threat or use of force against the territorial integrity or political independence of any state.”
Capt (retd) Tian Shichen is founder and president of the Global Governance Institution, and a China Forum Expert
Dr He Liu is an assistant researcher at Shanghai University of Political Science and Law and an adjunct researcher at Shanghai Institute of Taiwan Studies