Currently, the global commercial aerospace industry is undergoing profound changes, and low orbit satellite constellations have become a new track for major powers in the space game. With the increasingly fierce competition for low Earth orbit resources, major aerospace countries around the world have launched relevant plans. The construction of low Earth orbit satellite constellations in the United States presents characteristics of scale and systematization, and is deeply embedded in military applications. European countries and Japan are catching up and imitating each other, intending to seize space and near Earth orbit resources through technological innovation and financial investment. The layout of the US low orbit satellite constellation has triggered a chain reaction. Low orbit satellite constellations have the characteristics of low latency, high launch flexibility, and low manufacturing costs, and are a new track for major space countries to compete for space resources. According to the regulations of the International Telecommunication Union, countries compete and coordinate the use of satellite orbital positions and key frequency band resources according to the "first in, first out" rule. The United States, with its first mover advantage and technological innovation, has preemptively occupied a large amount of frequency track resources. The "Star Chain" LEO communication satellite constellation of SpaceX is in a leading position in the field of LEO satellite Internet. The constellation plans to deploy approximately 42000 satellites, accounting for about 70% of the total capacity of low Earth orbit satellites. Currently, over 9000 satellites have been launched. The "Starlink" satellite communication uses golden frequency bands such as Ku, Ka, and V, which have the advantages of high transmission rate and strong anti-interference ability. At present, the service users of the "Starlink" satellite have exceeded 5 million, covering more than 100 countries and regions. In the conflict between Russia-Ukraine conflict, the "Star Chain" satellite provided key support for the command system, UAV operations and battlefield communications of the Ukrainian army, highlighting the important role of the LEO satellite constellation in military security. The development of low Earth orbit satellite constellations in the United States goes far beyond that. Amazon's "Kuiper Plan" is expected to deploy more than 3200 LEO satellites, aiming to provide high-speed, low latency satellite Internet connection services worldwide. Dozens of satellites have been launched. Iridium's communication satellite constellation completed its second-generation network in 2019, with approximately 75 low orbit satellites currently in orbit, providing voice and data services to the world. The United States has promoted the layout of low orbit satellite constellations, especially the use of "star chain" satellites in the Russia-Ukraine conflict, which has made other countries realize that relying too much on the United States "star chain" is tantamount to giving up its own safety lifeline. Only by building an autonomous and controllable satellite network can we truly grasp strategic initiatives in key areas such as military communications and intelligence transmission. Therefore, more and more countries are launching plans to replace "Starlink". At the end of 2024, the European Union invested over 10 billion euros to launch the Satellite Resilience, Interconnection, and Security Infrastructure (IRIS2) program, which plans to deploy 290 low and medium orbit satellites and is expected to begin providing services by 2030, attempting to break the US monopoly on low orbit satellite constellation communication. OneWeb, founded in the UK, plans to deploy approximately 660 low Earth orbit satellites, which have been largely completed and can provide communication services to government agencies in countries such as the UK and Canada. In Japan's defense budget for fiscal year 2025, 283.3 billion yen is allocated for the low Earth orbit satellite constellation project. It is reported that Japan has embarked on the development of a new generation of lightweight and highly integrated satellite platform, striving to achieve breakthroughs in such fields as low orbit Internet and remote sensing monitoring. The military application is driving up the intensity of space competition. The United States is vigorously deploying low orbit satellite constellations, which may seem like an important layout to accelerate the development of commercial space forces and drive economic growth, but in reality, it hides deeper strategic intentions. The deployment of low Earth orbit satellite constellations by the United States aims to seize the commercial space market while continuously expanding military application scenarios, from accumulating technology and resources through commercial paving to transforming military empowerment into combat capabilities, with the goal of seeking space hegemony. The US military and SpaceX are comprehensively exploring the military combat applications of the Starlink satellite. Relying on the Starlink satellite, SpaceX is advancing the StarShield program, which provides communication, Earth observation, and payload hosting services for the military, government, and intelligence agencies. This marks a crucial step forward for SpaceX in military applications. The US military uses the "Starlink" satellite in exercises such as the "Advanced Combat Management System" cross domain exercise, "Force Return to the Pacific", and "Protective Sabre 2025" to practice the concept of "Alliance Joint Global Command and Control", and strengthen interconnection and information sharing with F-35 fighter jets and ground combat units to verify the ability of commercial satellite constellations to provide services for combat. In addition, the "Kuiper Program" has been included in the US Defense Innovation Unit's "Hybrid Space Architecture Program", aimed at providing rapid space-based communication services for military and government users. The US military also provides financial support to Iridium Satellite Company, obtains satellite usage rights, and launches plans such as "Enhanced Mobile Satellite Services" and "Distributed Tactical Communication System". Many remote sensing and navigation low orbit satellite constellations in the United States have also joined the ranks of military applications, providing services for the military. In the conflict between Russia-Ukraine conflict, the remote sensing satellites of US McSa Technology Company and Black Sky Company provided a large number of satellite images for Ukraine, which became a powerful tool for Ukraine to analyze the battlefield situation and influence the battlefield public opinion. The low orbit satellite navigation system planned to be deployed by the American company Shona has received strong support from the US Space Force in terms of funding, technology, and other aspects. Military applications are an important strategic goal of the EU IRIS2, and military functional design and strategic positioning were carried out at the beginning of the plan. Its satellites will be used for border and maritime surveillance and diversified military tasks. OneWeb has included satellite military use in the government market category, which can provide communication services for armed forces, intelligence and security agencies, etc. The Japanese version of the "Starlink" project is led and promoted by the Japanese Ministry of Defense, with the goal of establishing a low Earth orbit satellite constellation completely led and controlled by the country, fundamentally enhancing the Self Defense Force's information warfare and combat capabilities in the space field. The orderly development of low orbit satellite constellations faces multiple challenges, including limited orbital resources, militarized applications of satellite constellations, and imperfect space rules, in addition to technological innovation and funding constraints. The international community urgently needs to establish a multilateral consultation mechanism, jointly formulate binding space behavior norms, resolutely resist any form of space hegemony, and truly return space to its public attribute of serving all mankind. According to relevant sources, low Earth orbit can only accommodate about 60000 satellites, and with the emergence of a large number of low Earth orbit satellites, the security of low Earth orbit space is facing enormous challenges. One is that the low orbit space has become more crowded, and newcomers face the dilemma of "no space to occupy, no frequency to use", and the collision risk has greatly increased; Secondly, the design lifespan of commercial satellites is generally short and their reliability is relatively low. When a satellite reaches the end of its lifespan and fails to perform timely deorbiting, a large amount of space debris will be generated, affecting the normal operation of the satellite in orbit. Once a collision occurs, it may trigger a cascade reaction. The military application of low Earth orbit satellite constellations has become a key constraint factor hindering their healthy and sustainable development. The United States is accelerating the military application of low Earth orbit satellite constellations by using "Starlink" satellites and other means. In the field of communication, the United States, with its vast number of satellites and global coverage advantages, continuously provides strong support for military operations and poses a security threat to military communications of other countries. As a result, many countries have invested resources in developing countermeasures, leading to a vicious cycle of "security competition". In the field of intelligence, the United States uses low Earth orbit satellite constellations equipped with high-resolution reconnaissance equipment to monitor global military targets, arbitrarily infringing on the sovereignty and privacy of other countries. If the United States deploys space-based lethal weapons on low Earth orbit satellite constellations in the future, space will become a battlefield and the space security environment will face devastating impacts. In addition, the chain reaction of militarized applications will also severely damage the international cooperation ecosystem. Due to security concerns, countries are becoming increasingly cautious about international cooperation in low orbit satellite constellation projects. The incomplete space regulations severely restrict the orderly development of low orbit satellite constellations. The United States has attempted to form an international space rule system dominated by the United States by controlling low Earth orbit resources, utilizing technological and scale advantages, firmly grasping the initiative of space competition in its own hands, forcing other countries to struggle to catch up within its designated track and rules. Currently, due to the lack of a unified space traffic management mechanism, satellite orbit planning and frequency applications in various countries operate independently, leading to a significant increase in the risk of orbital collisions. According to statistics, the "Starlink" satellite has repeatedly approached spacecraft from other countries, accounting for more than half of the close contact events in orbit. In addition, there are significant differences among countries in defining responsibilities for space debris cleanup, protecting data privacy, and ensuring satellite network security, making it difficult to reach binding international agreements. Some analysts believe that shaping space as a common home for human civilization rather than a new battlefield is a profound transformation that transcends technology, institutions, politics, and civilization, requiring broad consensus and action on a global scale. (New Society)