I'm sorry...what fantasy land do you have to live in where you think it's ok to use a company social media account to promote your own politics not only without permission from the company, but an explicit denial.
By "your own politics" are we still referring to things like "hey it's not okay that you're making fun of people and their different-sounding names"?
Even if we're referring to this case. What right do you think you have to use company name to push your agenda? Even if you're morally right about the matter, you're morally wrong to use company entity to push your opinion. If you're uncomfortable with the company then go to management. If it doesn't work with management then leave and try to get your retribution or whatever bullcrap using your name.
It was with the best intentions to improve the world! ;)
There is nothing you can tweet that will improve the world. Lol