The maritime transport fleet is an important reserve force for national defense

Fleets of ocean-going shipping vessels have historically been used as logistical transport in wartime. The United States, Britain and other countries call the merchant fleet "the fourth branch of the military besides land, sea and air", and the merchant fleet of the former Soviet Union is also called the "shadow fleet" by Western countries. It can be seen that it played a role in the victory or defeat of the war. It is precisely because maritime transport occupies such an important position that all countries in the world attach great importance to maritime shipping, protect it through legislation, support and subsidize it financially, and give preferential treatment in cargo loading.