Superman 2

I don't get Superman 2. Actually, just one specific part. That giant cellophane 'S' he had? What the hell was that? Where did he get it? Why did he have it? Why did he use it then? Those were 3 super villains and what good would a paper 'S' do against them? Why didn't he use it on regular criminals? Wouldn't General Zod be the laughing stock of the universe if he was done in by a cellophane 'S'? Was it an emergency only 'S'? Color me confused.