Actually, I don't think it's a good idea to bring your politics into a an enclosed pace like this where people are forced to be a captive audience, notwithstanding that I agree with theparticular sentiment expressed.
> you have the right to express it
Out in public sure. In an airplane you're in someone else's private space (ie the airline's) and everyone is not only confined with you in minimal comfort, they have no way to leave. Trying to 'own' the space in this context is a dick move. If I'm a traveling passenger I don't want to be subject to your political ideas/religious sentiments/music preferences/sporting affiliation or whatever else. Besides the irritation it may or may not inflict on other passengers, it's an unnecessary burden for the flight crew, who are going to have to field any complaints about it.
In short, please stow your rights in the overhead container or in your checked baggage and respect other peoples' right to be left alone.