Left side highway

So, I never really thought about the reasons behind it before, but a while ago my friend Hannah told me about a theory as to why some countries have traffic moving on the left instead of the right. She explained it as the countries that were "sword carrying countries" (ie. England and Japan) had traffic on the left side.

Apparently, this is because in the way back days, before mechanized transport, people would walk down the street on the left. They walked on the left because people carried their sword on their left hip (either due to tradition or the vast majority of the population being right-handed) and so if you were going to fight someone, you wanted them to the right of you so you could draw your sword and defend or attack in one motion without bringing the sword back across your body.

Walking traffic rules became vehicle traffic rules and the rest, as they say, is history.

I kinda like traffic being on the right, so I'm glad America is a gun country.