Why every ones (most) take politics so superficially then go make stubborn claims with no proof but the media?

Some pplz are SO stubborn and opinionated while they have no proof and lots of them r just repeating what they hear . . . Like when a guy say that invading iraq was to liberate iraqi pplz this is a BULLSH!T ! Am speaking generally why every1 is so stubborn abt his political theories and why others trust the media so much ? Is there any logic behind that ? Like . . . When some1 say 9/11 was inside job others go 19 arabs . . . . Etc. Do u excpect a white CIA guy to fly the plan there ? In case it is right those arab amatures will be just puppets . . . Any one is getting my point ? I mean whenever we think we know the truth we find that there are deeper hidden layers any one agree with me ? Thx guy and feel free to criticize my grammer haha just be helpfull and tell me my mistakes so that i can avoid them later . . . Peace