why would japan need such fast trains? you can walk through the country in a matter of minutes
Japan has a massive amount of people, walking to in from work in a dense urban area is impractical. So about twice every day, once in the morning, and once in the evening. They all cram themselves into trains to the point where guards literally have to push more people in just to close the doors. These trains are almost historically never late as well. If one of these trains is ever late they give you a slip of paper to show to your boss or teacher because they won't believe you otherwise.
