美國向日本海軍基地派遣無人船，標誌著無人駕駛船在威懾中國方面發揮新作用

The United States recently dispatched two multi-role unmanned surface vessels (USVs), or drone ships, to its naval bases in Japan. This move, according to defence analysts, could be indicative of Washington's plans to incorporate drone ships into its deterrence strategy against Beijing over Taiwan. The two USVs, named the Mariner and Ranger, are part of the US Third Fleet. They embarked on their journey from California and arrived in Yokosuka, Japan, last month. This voyage was part of the US Navy's Integrated Battle Problem 23. 2 exercise (IBP23. 2), as stated by the US Seventh Fleet, which is headquartered in Yokosuka. Prior to their arrival in Yokosuka, the Mariner and Ranger made a stopover at the Indo-Pacific headquarters in Pearl Harbour, Hawaii. Here, two smaller USVs, the Hunter and Sea Hawk, had participated in another rehearsal the previous year. The IBP23. 2 exercise is primarily focused on testing the collaborative operation of USVs and manned vessels in the Indo-Pacific region. This marked the first instance of the US Navy deploying its driverless ships over such an extensive distance. The US Seventh Fleet reported that the Ranger was accompanied by the Arleigh Burke-class guided-missile destroyer USS Shoup during its Pacific crossing. Lu Li-shih, a former instructor at the Taiwanese naval academy in Kaohsiung, stated that the strategy of deploying drone boats alongside warships represents a novel approach in naval combat. This tactic mirrors the modern air combat strategy of pairing unmanned aerial vehicles (UAVs) with fighter jets during 'dogfights'. He further explained that the deployment of drone boats and UAVs is part of an offset strategy aimed at reducing the number of combatants in modern warfare, with the ultimate objective of minimising casualties. Lu also noted that the Ranger appears to have made stops in Guam and Okinawa, as evidenced by a photo published by the Japan Times last month. The photo displayed the ship's navigation path on a screen in its control room. Satellite imagery and the maritime traffic automatic identification systems of Guam and Okinawa revealed that the two USVs and the USS Shoup destroyer were operating in unison during their lengthy journey. The markings on the Mariner appeared to have worn off after enduring strong winds and waves on the high seas. The two drone boats were equipped with combinable weapons modules, including the US Navy's Standard Missile-6, which is capable of performing air defence, terminal ballistic missile defence, and anti-ship strike functions. The development of USVs was emphasised in the Pentagon's replicator initiative, a military tech innovation plan announced by US Deputy Secretary of Defence Kathleen Hicks in August. The plan outlines the Pentagon's aim to develop thousands of UAVs, a move seen as a response to the rapid increase in Chinese warships in recent decades. According to the Rand Corporation, the US continues to possess the world's most powerful navy, with a combined tonnage of approximately 4. 6 million tonnes. However, it only has around 280 warships, compared to China's 425 active warships as of August 2023. The Pentagon anticipates this number to rise to 440 by 2030. The US Navy's Chief of Naval Operations (CNO) Navigation Plan 2022 proposes that the American naval fleet should expand to about 523 ships by 2045, comprising 373 manned ships and 150 unmanned ships. Lu stated that it would be impossible for the American shipbuilding industry to match China's capacity to mobilise an entire nation for a single task. He suggested that the replicator initiative and the IBP exercises, the first of which was conducted in May, represent Washington's best options for catching up with Beijing. Scott Savitz, a military expert at the Rand Corporation, proposed that Taiwan should collaborate with the US to launch swarms of explosive USVs to deter Beijing from attacking the self-ruled island. The Ukraine war has demonstrated the effectiveness of explosive USV technology. Savitz noted that while Ukraine has received support from Starlink, the satellite internet network operated by SpaceX, Taiwan lacks its own satellite network to facilitate communication and connection between drones and unmanned ships. However, he believes this obstacle can be surmounted. Savitz stated that the US military possesses the necessary capabilities, which it could potentially enable Taiwan to utilise. Furthermore, he suggested that the required volume of communications will likely decrease as USV autonomy becomes more advanced. Beijing considers the self-ruled island of Taiwan as part of its territory, which it intends to reclaim – by force if necessary. Most countries, including the United States, do not recognise Taiwan as an independent state, but are opposed to any unilateral alteration of the cross-strait status quo by force. China has also made significant advancements in USV technology. Last year, the state-owned China State Shipbuilding Corporation unveiled a model of a 340-tonne multipurpose unmanned combat surface vessel (UCSV) with a maximum speed of 42 knots and a range of 4,000 nautical miles (approximately 7,410km), as reported by Janes Defence News. A photo released by the China State Shipbuilding Corporation earlier this year depicted a smaller USV prototype equipped with highly advanced radar. The radar systems will render the drone boat more difficult to detect, thereby enabling it to accurately strike targets when operating as a 'suicide vessel' or conducting close-in reconnaissance. However, Savitz asserted that the US Navy, which has more real combat experience than its Chinese counterpart, possesses certain advantages in the development of USV technology. He stated that any precise assessment of the relative strengths of various systems would be classified. He noted that China is claiming some successes, although he has long observed that authoritarian systems are more prone to exaggerating military capabilities than democracies.