"Your letter in the paper..."

"Mmm?"
"He didn't like it."
"I can't imagine he did," I said.
I had been accosted by someone in the university grounds - the sort of person who  is determined to tell me what he or she thinks. This time though he was keen to tell me what a certain politician thought. 
He happens to live close to the certain politician. They don't get on together. The person talking to me is a Labor man through and through. His Dad and his Grandad were Labor men. He married a woman whose father was a Labor man. He toyed with the idea of running for parliament himself at one time. His wife stopped him. She might vote Labor (I don't know but assume this to be the case) but she didn't want to be married to a politician.
The certain politician is left of Labor. He's the sort of politician who will form a coalition with the Labor party if it means them getting into power but  he will demand a great deal in return. I hope it doesn't happen. I would prefer one side or the other to win enough seats to govern in their own right.
But, the pollie doesn't like me. One of his staffers phoned me once to try and tell me that I was wrong and that I "shouldn't be writing letters like that". (Just over a week later what I had "predicted" in the letter came to pass...but I admit I had a little inside information.) I am not going to be put off by people telling me I shouldn't be doing something like that. 
Letters are still powerful things. An e-mail is still not the same as a letter on paper. Of course my "letters to the editor" are e-mails these days. I also e-mail many other people. It usually works  because the person at the other end will know me, know of me, or will have requested a reply from me. All that is different but, if I want to make an impact, I will write a letter on paper. I will post it.  There are certain rules to be followed. The letter needs to be short - no more than a page if at all possible. It needs to be polite and to the point. Opinion needs to be backed with verifiable facts. All those things work towards people reading it and taking notice of it.
I am not sure what the psychology is but I know that the paper letter written like this will still make a bigger impact - and that letters e-mailed to the editor which appear in the paper work too.
Is it something to do with....paper?