Khaled Aly Thanks for replying. Sure, allowing anyone to reply to any tweet anywhere promotes spam, bots, and gives undue weight to people. Even here on Medium, I control the responses to my post. Twitter would be just fine without any visibility being given to those non-connected responses. If another user had a comment or retweeted something with comment then their followers would see that just as if someone overheard some news and then shared it with a different set of people. Twitter can easily eliminate the mechanisms by which mobs attack online and by which random folks immediately pollute any given thread.