The Japanese Civil War was important for many reasons. It was important because without it, the Japanese people wouldn't have been able to gain freedom from dictatorship rule. Also very importantly, the Japanese would not have been able to get rid of the class system. If the war had not have happened, there would probably still be samurai.
Soon after the war, a law was made prohibiting the use of or even carrying around a sword. And lastly, speaking on a personal interest of mine, I have enjoyed how the Japanese people popularized the Japanese Civil War in Anime (Japanese animated TV shows / movies ), manga (Japanese comic books), and even video games making fictional stories based on the real historical facts of the Japanese Civil War. The civil war for Japan was so important because had it not happened, modern Japan as we know it today would probably not have happened. Japan's capital was moved to Edo, which was later called Tokyo. Japan developed into a modern industrial and military power, the Meiji leaders encouraged industrialization, set up required education and schools, and turned to Western countries for new ideas and technology. Railroads, modern systems of banking and taxation were made.
Most importantly, Japan's Constitution was set up along with a two-house parliament called a Diet. Just as the civil war for the United States changed the whole makeup of our country, Japan's Civil War would forever change and set up a modern Japan, one that would be an outstanding country and true leader in our world.