I believe that Judas was looking for Jesus to set up an earthly kingdom, overthrow Rome, etc, so to usher it in, Judas betrayed Jesus. Judas’ thinking might have been that if Jesus was who He said He was, He wouldn’t be allowed to be crucified and if Jesus wasn’t who He said He was then Jesus wasn’t the messiah anyway. Judas just didn’t understand what Jesus had to do to save mankind (through His death, burial and resurrection). It wasn’t about an earthly kingdom but a spiritual purpose.