It's three letters in. "H".
The Middle. That way, you're always driving out of Iowa.
Someone stops you in the middle of the road and asks you to tell him a good joke, What would be your reply?
an Envelope EDIT: My deepest Canadian apologies to those who are calling this a riddle. I always took it as a cheesy joke
Pen Gwyn !
They're not infallible
Hallmark. God cares enough to send the very best.