The ocean is rich in biological resources, space resources, energy resources and mineral resources. In modern history, western countries invaded and plundered other countries by sailing. Old China was invaded by foreign enemies repeatedly because it had no maritime defense. With the continuous depletion of the world's land resources, people have set their sights on the ocean for development. Today, many territorial disputes are related to the sea, such as the British-Amama War, the Diaoyu Islands dispute between China and Japan, the Gulf War and the South China Sea issue. Therefore, it is of great significance to maintain the surrounding security and defend the maritime territory.

1. The key to defending marine land lies in increasing investment in science and technology. At present, many western countries have more than one aircraft carrier, which is used to safeguard territorial sovereignty and carry out foreign wars. The US government even regards the number of aircraft carriers dispatched as a sign of tension between the two countries (one aircraft carrier dispatched by the US government is equivalent to warning other countries, and three aircraft carriers are equivalent to declaring war). At present, only one aircraft carrier in China is modified from a foreign ship.

2, to defend the maritime territory, but also to increase law enforcement and management. Russian President Vladimir Putin once said: "The territorial issue is not negotiable." Although peace and development have become the theme of the times, the law of the jungle is still a universal principle in handling international affairs because western countries still dominate international affairs. Therefore, China's protests and negotiations are invalid, and the best way is to strengthen military patrols and other tough measures.