Nationalism in moderation is just called patriotism. It's only a problem when it goes overboard into nativism. Denying negative aspects is very different from putting them into the context of setting and even human nature. In terms of dissent, force is only appropriate when used to combat force. Also, have you seen the hypocrisy of ACAB people asking for help from police, despite their rhetoric? Pretty sure that Hong Kong protesters would never call for help from CCP enforcers.