You are a top Hollywood Casting Director who has a huge blockbuster movie to cast. About an insane corrupt "leader". Whom do you select?

Who could play that role most superbly in your opinion? A malevolent revengeful unattractive man who is always the victim and never responsible accountable for anything. He suffers from feeling extremely inadequate all the time and he is in reality a very inadequate man who has felt "less than" his entire life.

Which actor can play EVIL CORRUPT and inadequate best?