It's Wednesday and time for another Everyday Etiquette question.
Today's question is a complicated one as it involves ordinary civility and driving. And, I've got to be honest here. I'm not entirely sure whether my question concerns the rules of the road or the rules of social behavior.
Today we're on an interstate highway much like the one pictured above. There are two lanes traveling East, and two heading West. You're in the right hand lane, having just merged onto the highway. In front of you is a semi truck going 60 miles an hour. The speed limit is 70 and, well, you have someplace to go. In the left hand lane a line of approximately 20 cars speed past you at 80 miles an hour. You put on your signal and wait to merge into the left hand lane.
While waiting to merge, a car pulls in behind you. When the 20-car stream in the left hand lane finally blows past, the car behind you merges into the left, cutting you off and ignoring your signal.
So here's my question: Is this rude or is this an example of the rules (official or otherwise) of the road?