One of The Five Pillars of Wikipedia is

Neutrality: Wikipedia is an Encyclopedia and as such has a policy of transmission and dissemination of knowledge. Ideally, any kind of political activism and/or propaganda is prohibited from the website and articles that deal with current events as they are unfolding always have a disclaimer that the neutrality of the said article is disputed and in extreme cases that involve an edit war, administrative intervention becomes inevitable and the party found to be in violation of Wikipedia's rules is blocked or even banned.