as amusing as these memes are, they are not really very accurate.
I'm sure he was not claiming that he was confusing a fire alarm with a doorknob. He most likely is trying to claim he thought it was one of those handicap buttons that automatically opens the door.
It doesn't really excuse his behavior, in fact an image of him confusing a handicap button with a fire alarm would be even more amusing.
But memes like this only show how desperate the right is to try to make SOMETHING to insult Democrats.
Tech tip: You don't really have to work that hard to insult or embarrass a democrat. Just wait 5 minutes and they'll do it for you.