Members of parliament are supposed to be the most diplomatic folks. Always solving differences via dialog. But for issues they feel strongly about, differences can be resolved using violence and that's what exactly happened in Japanese parliament. They were voting for a bill that would allow Japan to use its military in defense of allies if there is no threat to Japan. One group wanted the bill to passed while another wanted to delay the voting. Since they couldn't agree, there was a fight but the bill was passed anyway.
That was the leading news story with video on NHK's morning news (11 pm EDT). It was quite the scene.
Politicians are passionate people too and militarization is a big issue in Japan since the 2nd World War. I wouldn't think much of it though because it seemed like the strong emotions came from a good place but violence is still wrong.
In South Korea the politicians hate each other so much that fights in parliament are regular thing out there. If you can't discuss something with someone you hate there's but one thing left to do. Either walk out or fight him. They choose the latter. Same thing happens in India I've heard. I wonder what sort of example these MPs who are supposed to be good role models set.
Japan has this happen frequently, but it is rarely a full brawl like that one was. it doesn´t happen in the USA since almost everyone in congress isn´t really passionate about anything. They talk the talk in front of cameras, but when it comes to actually writing laws and voting, there are no suprises and there is no debate, because nobody is going to change their minds no matter what you say.
I wonder if it is on youtube? Our congress has their share of disputes, but as far as I know in recent history, brawls haven't started on the floor of Congress but it has happened in the past. Some political disputes have stared on the floor of the House and I think some legislators have hit others with their canes.