從國際法檢視中國大陸軍艦與軍事航空器繞臺行為之部分法律議題

An Examination on Certain Legal Issues Arising from China’s Military Activities Surrounding the Waters and Superjacent Airspace of Taiwan in the Eyes of International Law

中國大陸軍艦在臺灣周邊的航行路線以及軍事航空器飛越路線，引起各界顧慮。臺灣基於國家安全因素，早劃有「臺灣防空識別區」，尤其兩岸特殊關係，不可能無視中國大陸軍艦與航空器任何接近臺灣舉止，本文檢視中國大陸此等行為的部分法律問題，以及臺灣是否可採取相對應措施。本文認為：因臺灣海峽非屬適用過境通行制度之海峽，故臺灣在領海部分享有主權，對進行情報蒐集且非屬無害通過之軍艦，得根據具體的狀況採取適當反制措施。在臺灣領空部分，無義務容忍他國航空器飛行，對於威脅程度較高且拒絕離開的軍用航空器，得以使用武力排除。而專屬經濟區水域及其上空部分，在西方學界通論認為在未涉及使用武力之前提下，外國軍艦或軍用航空器在沿海國專屬經濟區的軍事行動，屬於得合法行使之自由，故而中國大陸有權利在臺灣的專屬經濟區與其上空進行軍事活動。此外，臺灣雖在領海外設有防空識別區，然此並非將外國航空器置於該區管轄，而是以「自衛權」為法源基礎，將防空識別區作為判斷是否危害國防安全的標準，並進一步決定是否行使自衛權。若未涉及使用武力，國際法並未限制沿海國得採行之措施；若涉及使用武力，須視對沿海國重要利益造成之危害大小，以及是否有其他可使用且有效之非武力措施而為判斷。 By encircling Taiwan, the navigation of Chinese warships and overflightsof Chinese military aircraft pose major concerns. Taiwan would never ignoreany operation of Chinese warships and military aircraft near Taiwan, notonly because it has long established the Taiwan Air Defense IdentificationZone (''Taiwan ADIZ'') for matters of national security, but in particular,the nature of cross-strait relations. Against this backdrop, this article examines some legal issues arising from China’s acts and the legalityof measures taken by Taiwan accordingly.This article concludes as follows. While the regime of transit passagedoes not apply to the Taiwan Strait, Taiwan enjoys sovereignty over itsterritorial sea. Hence, Taiwan is entitled to respond appropriately againstforeign warships conducting intelligence gathering, which does not enjoy theright of innocent passage. Further, Taiwan is not obligated to tolerateunauthorized foreign aircrafts entering its national airspace. Thus, it mayuse armed force against such military aircraft, when it presents high levelof threats and refuses to leave. As far as the exclusive economic zone (''EEZ'') and the airspace over it are concerned, the predominated view ofwestern scholars argues that military operations of foreign warships or militaryaircraft are internationally lawful uses of the sea, provided they do not involvethe use of force. Therefore, China is entitled to conduct military activitiesin Taiwan’s EEZand airspace above it. Moreover, Taiwan does not intendto exercise jurisdiction over every foreign aircraft entering its ADIZ, whichextends beyond the national airspace. Instead, the Taiwan ADIZserves as abenchmark for Taiwan to determine dangers to national security and a criterionto exercise the right to self-defense. International law imposes no limitationon actions taken by coastal States in exercising the right to self-defense, solong as these actions do not constitute use of force. On the other hand, thelegality of use of force by coastal States is conditioned upon the magnitudeof endangered vital interests and the availability of effective and feasiblealternatives, which do not involve the use of force.