Chinese netizens have come up with a new trick to sanction Japan: imitating Russia by completely closing Chinese airspace and not allowing Japanese planes to pass through. This way, if Japanese flights want to go to the West or Africa, they would have to detour at least 2/3 of the globe!

This idea sounds quite satisfying at first, as airspace is an important component of national sovereignty. Closing airspace can indeed impose direct constraints on countries that rely on flight routes; Russia's previous closure of airspace made European airlines pay a huge price.

However, if this trick is to be put into practice, people may not realize that the international rules, economic impacts, and practical feasibility involved are much more complex than imagined, and it is not as simple as saying 'close' to solve the problem.

First, it must be made clear that Japan's aviation industry is indeed highly dependent on Chinese airspace, and this judgment by netizens is not mistaken.

From the perspective of flight route layout, flights from major Japanese cities such as Tokyo and Osaka to Europe and Africa must cross Chinese airspace on the shortest routes, saving at least 4 hours of flight time and reducing nearly 30 tons of fuel consumption on a one-way trip.

Japan Airlines and ANA, the two main airlines, have chosen routes that cross Chinese airspace for 85% of their flights to Europe in 2024, which carry nearly 60% of the air passenger traffic and 40% of the air cargo volume between Japan and Europe.

If China really closes its airspace completely, Japanese flights would have to detour, either north around the Russian Far East and Arctic routes or south around Southeast Asia and the Indian Ocean; no matter which route is chosen, they would have to fly thousands of kilometers more.

If detouring north, the Arctic route is greatly affected by climate, and normal navigation is impossible during the winter ice period. Moreover, Russia strictly controls the Arctic route, and Japanese flights would have to pay high transit and security fees to use it.

Detouring south would involve passing through the Malacca Strait, Suez Canal, and other chokepoints, where the navigation density is already high, making congestion very likely. Additionally, the longer journey would extend the one-way flight time to over 15 hours, which is a huge test for both crew and passengers.

More critically, the surge in operating costs is alarming. Japan Airlines has calculated that if flights detour without passing through Chinese airspace, the fuel cost for a one-way flight would increase by over 60%. Coupled with crew overtime subsidies, aircraft depreciation, and other additional expenses, the losses for a single flight could exceed 1 million RMB.

In 2024, the Japanese aviation industry has just recovered from the pandemic, with a net profit of only 120 billion yen for the entire year. If detouring becomes a long-term solution, the two main airlines could very likely fall back into losses, and smaller airlines might face direct bankruptcy.

But let’s not forget that closing airspace has always been a double-edged sword. While it strikes at Japan, it would also have a significant impact on our own country. This is the core reason why this proposal needs careful consideration.

China's civil aviation industry also has a large number of flights between Japan and China. In 2024, our airlines such as Air China and China Eastern have over 180,000 flights to Japan, carrying nearly ten million passengers and hundreds of thousands of tons of cargo.

If airspace is closed, our flights would also be unable to take off or land normally at Japanese airports, leading to direct economic losses for the civil aviation industry and significantly affecting personnel exchanges and trade cooperation between China and Japan.

A large portion of the air cargo between China and Japan consists of electronic components and precision instruments, which are highly time-sensitive. A disruption in the transport of these goods would directly affect the production of the electronics manufacturing industry in regions such as the Yangtze River Delta and the Pearl River Delta.

From the perspective of international rules, there are strict legal definitions regarding airspace closures. According to the Convention on International Civil Aviation, countries may not arbitrarily close their airspace unless for special reasons such as national security, and they cannot impose discriminatory airspace restrictions targeting specific countries.

If our country unilaterally closes airspace against Japan, it may trigger disputes in the international community, and some countries may follow suit with retaliatory measures, affecting our aviation companies' route layouts worldwide.

The closure of airspace by Russia was done in a context of special geopolitical conflict and involved reciprocal countermeasures. Europe had first imposed airspace restrictions on Russia, prompting Russia's response, which is fundamentally different from the netizens' proposal to actively close the airspace.

Another point that is easily overlooked is the impact on third-country flights. Many third-country flights to China also pass through routes near Japanese airspace. If our country closes its airspace, it could trigger a chain reaction, affecting the normal operation of the global aviation network.

The International Air Transport Association has issued a warning that if restrictions are imposed on Sino-Japanese airspace, the turnover efficiency of global air cargo would drop by more than 15%, and international oil prices could rise due to increased demand from detoured routes.

From a practical standpoint, the difficulty of fully closing airspace is also quite high. China’s airspace is vast, and the air routes adjacent to Japan are dense. Achieving comprehensive control would require a significant investment of air traffic management resources and military forces.

Moreover, once the airspace is closed, it would be necessary to handle a large number of flights that are already en route, coordinating these flights to divert and return, to avoid aviation safety accidents, which would be a huge test for the civil aviation dispatching system.

The netizens' proposal aims to counter some of Japan's inappropriate behaviors through effective means, and this patriotic sentiment is commendable. However, sanctions and countermeasures between countries have always required precise policy implementation, balancing effectiveness and our own interests.

In fact, besides closing airspace, our country has many more precise countermeasures available, such as implementing export controls in areas where Japan is dependent, like rare earths and high-end manufacturing equipment. These measures can accurately target Japan's weaknesses while minimizing impacts on our own interests.

Ultimately, closing Chinese airspace may seem like a "trump card," but the actual implementation costs are too high and could trigger a series of uncontrollable chain reactions.