No------ rationality doesn't HAVE to be cancelled out by bias...

No------ rationality doesn't HAVE to be cancelled out by bias ......however I'm surprised you never mentioned your own bias which seems extreme .....which leads you to often , quite irrationaly depart from the topic of the Ukraine war to talk about Yugoslavia .

rational moral people don't support this war of aggression and russian expansion .
Supporters of this war do so on the basis of either ethnicity or hatred of the US OR for political reasons such as trump support .....I find this motivation far from rational .